KID31 and antibodies that bind thereto

ABSTRACT

The invention provides the identification and characterization of disease and cancer-associated antigen, KID31. The invention also provides a family of monoclonal antibodies that bind to antigen KID31, methods of diagnosing and treating various human cancers and diseases that express KID31.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application Ser.No. 60/643,757, filed Jan. 12, 2005, which is incorporated in itsentirety by reference.

TECHNICAL FIELD

This invention is in the fields of biology and immunotherapy. Morespecifically, it concerns the discovery that carboxypeptidase M, a knownantigen, is associated with a variety of human cancers and relateddisease. The invention further provides for the diagnosis and/ortreatment of a variety of human diseases and cancers associated withcarboxypeptidase M using antagonists, modulators and peptides that bindto carboxypeptidase M, including anti-carboxypeptidase M antibodies.

BACKGROUND OF THE INVENTION

Human carboxypeptidase M is a membrane-bound metalloprotease-peptidethat specifically cleaves carboxyl terminal arginine or lysine residuesfrom peptides or proteins. Carboxypeptidase M is a glycoprotein with amolecular weight at around 62 kDa and is a member of a family ofregulatory metallo-carboxypeptidase proteins.

Carboxypeptidase M is widely expressed on a variety of human tissues andis believed to play a role in the control of peptide hormones and growthfactor activity at the cell surface and in the membrane-localizeddegradation of extracellular proteins (Reverter et al., J. Mol. Bio.Vol. 338, pp. 257-269 (2003)). Using carboxypeptidase M-specificantibodies, researchers have identified carboxypeptidase M as a markerfor macrophage maturation.

Despite being described as a marker for macrophage maturation, there islittle data to show any correlation between carboxypeptidase Mexpression and cancer. Carboxypeptidase M expression has been reportedin a patient with a granulomatous reaction within a conventional clearcell renal cancer using immunohistochemical techniques and an antibodyspecific for carboxypeptidase M (Kovacs et al., Pathology Oncology Res.,Vol. 10, No, pp. 169-171 (2004)).

In addition to their known uses in diagnostics, antibodies have beenshown to be useful as therapeutic agents. For example, immunotherapy, orthe use of antibodies for therapeutic purposes has been used in recentyears to treat cancer. Passive immunotherapy involves the use ofmonoclonal antibodies in cancer treatments. See for example, Cancer:Principles and Practice of Oncology, 6^(th) Edition (2001) Chapt. 20 pp.495-508. These antibodies can have inherent therapeutic biologicalactivity both by direct inhibition of tumor cell growth or survival andby their ability to recruit the natural cell killing activity of thebody's immune system. These agents can be administered alone or inconjunction with radiation or chemotherapeutic agents. Rituximab andTrastuzumab, approved for treatment of non-Hodgkin's lymphoma and breastcancer, respectively, are two examples of such therapeutics.Alternatively, antibodies can be used to make antibody conjugates wherethe antibody is linked to a toxic agent and directs that agent to thetumor by specifically binding to the tumor. Gemtuzumab ozogamicin is anexample of an approved antibody conjugate used for the treatment ofleukemia. Monoclonal antibodies that bind to cancer cells and havepotential uses for diagnosis and therapy have been disclosed inpublications. See, for example, the following patent applications whichdisclose, inter alia, some molecular weights of target proteins: U.S.Pat. No. 6,054,561 (200 kD c-erbB-2 (Her2), and other unknown antigens40-200 KD in size) and U.S. Pat. No. 5,656,444 (50 kD and 55 kDoncofetal protein). Example of antibodies in clinical trials and/orapproved for treatment of solid tumors include: Trastuzumab (antigen:180 kD, HER2/neu), Edrecolomab (antigen: 40-50 kD, Ep-CAM), Anti-humanmilk fat globules (HMFG1) (antigen >200 kD, HMW Mucin), Cetuximab(antigens: 150 kD and 170 kD, EGF receptor), Alemtuzumab (antigen: 21-28kD, CD52), and Rituximab (antigen: 35 kD, CD20).

The antigen targets of trastuzumab (Her-2 receptor), which is used totreat breast cancer, and cetuximab (EGF receptor), which is in clinicaltrials for the treatment of several cancers, are present at somedetectable level on a large number of normal human adult tissuesincluding skin, colon, lung, ovary, liver, and pancreas. The margin ofsafety in using these therapeutics is possibly provided by thedifference in the level of expression or in access of or activity of theantibody at these sites.

Another type of immunotherapy is active immunotherapy, or vaccination,with an antigen present on a specific cancer(s) or a DNA construct thatdirects the expression of the antigen, which then evokes the immuneresponse in the individual, i.e., to induce the individual to activelyproduce antibodies against their own cancer. Active immunization has notbeen used as often as passive immunotherapy or immunotoxins.

Several models of disease (including cancer) progression have beensuggested. Theories range from causation by a singleinfective/transforming event to the evolution of an increasingly“disease-like” or ‘cancer-like’ tissue type leading ultimately to onewith fully pathogenic or malignant capability. Some argue that withcancer, for example, a single mutational event is sufficient to causemalignancy, while others argue that subsequent alterations are alsonecessary. Some others have suggested that increasing mutational loadand tumor grade are necessary for both initiation as well as progressionof neoplasia via a continuum of mutation-selection events at thecellular level. Some cancer targets are found only in tumor tissues,while others are present in normal tissues and are up regulated and/orover-expressed in tumor tissues. In such situations, some researchershave suggested that the over-expression is linked to the acquisition ofmalignancy, while others suggest that the over-expression is merely amarker of a trend along a path to an increasing disease state.

An ideal diagnostic and/or therapeutic antibody would be specific for anantigen present on a large number of cancers, but absent or present onlyat low levels on any normal tissue. The discovery, characterization, andisolation of a novel antigen that is specifically associated withcancer(s) would be useful in many ways. First, the antigen could be usedto make monoclonal antibodies against the antigen. An antibody wouldideally have biological activity against cancer cells and be able torecruit the immune system's response to foreign antigens. An antibodycould be administered as a therapeutic alone or in combination withcurrent treatments or used to prepare immunoconjugates linked to toxicagents. An antibody with the same specificity but with low or nobiological activity when administered alone could also be useful in thatan antibody could be used to prepare an immunoconjugate with aradio-isotope, a toxin, or a chemotherapeutic agent or liposomecontaining a chemotherapeutic agent, with the conjugated form beingbiologically active by virtue of the antibody directing the toxin to theantigen-containing cells.

One aspect desirable for an ideal diagnostic and/or therapeutic antibodyis the discovery and characterization of an antigen that is associatedwith a variety of cancers. There are few antigens that are expressed ona number of types of cancer (e.g., “pan-cancer” antigen) that havelimited expression on non-cancerous cells. The isolation andpurification of such an antigen would be useful for making antibodies(e.g., diagnostic or therapeutic) targeting the antigen. An antibodybinding to the “pan-cancer” antigen could be able to target a variety ofcancers found in different tissues in contrast to an antibody against anantigen associated with only one specific type of cancer. The antigenwould also be useful for drug discovery (e.g., small molecules) and forfurther characterization of cellular regulation, growth, anddifferentiation.

What is needed are novel targets on the surface of diseased and/orcancer cells that may be used to diagnose and treat such diseases and/orcancers with antibodies and other agents which specifically recognizethe cell surface targets. There exists a further need, based on thediscoveries disclosed herein, for novel antibodies and other agentswhich specifically recognize targets on the surface of cells that canmodulate, either by reducing or enhancing, the disease-promotingactivities of carboxypeptidase M. It is an object of this invention toidentify antagonists of human carboxypeptidase M that are capable ofinhibiting its disease-associated activities. It is another object toprovide novel compounds for use in the assay of carboxypeptidase M, andfor use as immunogens or for selecting anti-human carboxypeptidase Mantibodies.

As will be described in more detail below, the present inventors havediscovered a known antigen, carboxypeptidase M, which we refer to hereinas KID31, identified as the antigen target of the novel antagonists,modulators and antibodies provided herein.

SUMMARY OF THE INVENTION

The invention disclosed herein concerns the discoveries that the knownantigen, carboxypeptidase M (KID31), is present on a variety of bothprimary and metastatic human cancers, and that anti-KID31 antibodies maybe used to treat such cancers. The invention provides for KID31antagonists, modulators, and monoclonal antibodies that bind to KID31,which is expressed on a variety of human cancers.

In another aspect, the invention is a monoclonal antibody anti-KID31that is produced by the host cell line KIDNEY.5.4B8.1A4 deposited onJan. 12, 2005 at the American Type Culture Collection with a PatentDeposit Designation of PTA# 6516.

In yet another aspect, the invention is a method of generatingmonoclonal antibody anti-KID31 reactive with diseased and/or cancerouscells comprising the steps of: (a) immunizing a host mammal with animmunogen; (b) obtaining lymphocytes from the mammal; (c) fusinglymphocytes (b) with a myeloma cell line to produce a hybridoma; (d)culturing the hybridoma of (c) to produce monoclonal antibodies; and (e)screening the antibodies to select only those antibodies which bind todiseased and/or cancerous cells or cell lines but do not bind tonon-cancerous or normal cells or cell lines, or bind to normal cells ata lower level or in a different fashion.

In another aspect, the invention is a method of generating an anti-KID31antibody comprising culturing a host cell encoding such antibody orprogeny thereof under conditions that allow production of the antibody,and purifying the anti-KID31 antibody.

In another aspect, the invention provides methods of generating any ofthe antibodies (or polypeptides) described herein by expressing one ormore polynucleotides encoding the antibody (which may be separatelyexpressed as a single light or heavy chain, or both a light and a heavychain are expressed from one vector) in a suitable cell, generallyfollowed by recovering and/or isolating the antibody or polypeptides ofinterest.

In another aspect, the invention is an anti-KID31 antibody or apolypeptide (which may or may not be an antibody) that competitivelyinhibits preferential binding of an anti-KID31 antibody to KID31. Insome embodiments, the invention is an antibody or a polypeptide (whichmay or may not be an antibody) that binds preferentially to the same ordifferent epitope(s) on KID31 as other anti-KID31 antibodies.

In another aspect, the invention is an KID31 modulator (which may or maynot be a polypeptide) that competitively inhibits preferential bindingof an anti-KID31 antibody to KID31. In some embodiments, the inventioncan be a small molecule or chemical compound that binds preferentiallyto the same or different epitope(s) on KID31 as other anti-KID31antibodies.

In yet another aspect, the invention is a composition comprising KID31bound by an antibody specific for an epitope of KID31. In oneembodiment, the antibody is anti-KID31. In other embodiments, two ormore anti-KID31 antibodies are administered, with such antibodiesmapping to two or more different epitopes on KID31. In some embodiments,the anti-KID31 antibody is linked to a therapeutic agent or a detectablelabel.

In another aspect, the invention is an antibody comprising a fragment ora region of an anti-KID31 antibody. In one embodiment, the fragment is alight chain of the antibody. In another embodiment, the fragment is aheavy chain of the antibody. In yet another embodiment, the fragmentcontains one or more variable regions from a light chain and/or a heavychain of the antibody. In yet another embodiment, the fragment containsone or more complementarity determining regions (CDRs) from a lightchain and/or a heavy chain of the antibody.

In another aspect, the invention provides polypeptides (which may or maynot be antibodies) comprising any of the following: (a) one or more CDRs(or fragments thereof) from the light or heavy chain; (b) three CDRsfrom the light chain; (c) three CDRs from the heavy chain; (d) threeCDRs from the light chain and three CDRs from the heavy chain; (e) thelight chain variable region; (f) the heavy chain variable region of theanti-KID31 antibody.

In another aspect, the invention is a humanized antibody. In someembodiments, the humanized antibody comprises one or more CDRs of anon-human anti-KID31 antibody. In some embodiments, the humanizedantibody binds to the same or different epitope(s) as other anti-KID31antibodies. Generally, a humanized antibody of the invention comprisesone or more (one, two, three, four, five, six or fragments thereof) CDRswhich are the same and/or derived from the CDR(s) of the originalnon-human anti-KID31 antibody. In some embodiments, the human antibodybinds to the same or different epitope(s) as other anti-KID31antibodies. In another aspect, the invention is a chimeric antibodycomprising variable regions derived from variable regions of a heavychain and a light chain of a non-human anti-KID31 antibody and constantregions derived from constant regions of a heavy chain and a light chainof a human antibody.

In another aspect, the invention is an isolated polynucleotide thatencodes an antibody mu-anti-KID31 that is produced by a host cell with adeposit number of ATCC PTA# 6516, or progeny thereof. This inventionencompasses antibody polypeptides having the inherent binding orbiological activities of any of the above-specified antibodies. Inanother aspect, the invention provides polynucleotides encoding any ofthe antibodies (including antibody fragments) as well as any otherpolypeptides described herein.

In another aspect, the invention is a pharmaceutical compositioncomprising any of the polypeptides (including any of the antibodiesdescribed herein) or polynucleotides described herein, such aspharmaceutical compositions comprising an anti-KID31 antibody linked toa chemotherapeutic agent, an antibody comprising a fragment of ananti-KID31 antibody, a humanized antibody of a non-human KID31 antibody,a chimeric antibody comprising variable regions derived from variableregions of a non-human anti-KID31 antibody and constant regions derivedfrom a human antibody, or a human antibody with one or more propertiesof a non-human anti-KID31 antibody, or of the anti-KID31 antibodydescribed herein linked to a chemotherapeutic agent (such as aradioactive moiety), and a pharmaceutically acceptable excipient.

In one aspect, the invention is a composition comprising an anti-KID31antibody bound to KID31 present on a diseased or cancerous cell. Inpreferred embodiments, the cancer cell is selected from the groupconsisting of kidney, ovarian, lung, prostate, pancreatic, colon, andbreast cancer cells. In some embodiments, the cancer cell is isolated.In some embodiments, the cancer cell is in a biological sample.Generally, the biological sample is from an individual, such as a human.

In another aspect, the invention is a method of diagnosing disease in anindividual by detecting KID31 on cells from the individual, particularlydiseases or disorders associated with inflammatory or autoimmuneresponses in individuals. In other aspects of the invention, methods areprovided for modulating inflammatory or autoimmune responses inindividuals. Diseases and conditions resulting from inflammation andautoimmune disorders that may be subject to treatment using thecompositions and methods of the invention include, by way ofillustration and not of limitation, multiple sclerosis, meningitis,encephalitis, stroke, other cerebral traumas, inflammatory bowel diseaseincluding ulcerative colitis and Crohn's disease, myasthenia gravis,lupus, rheumatoid arthritis, asthma, acute juvenile onset diabetes, AIDSdementia, atherosclerosis, nephritis, retinitis, atopic dermatitis,psoriasis, myocardial ischemia and acute leukocyte-mediated lung injury.

Still other indications for therapeutic use of antibodies and othertherapeutic agents of the invention include administration toindividuals at risk of organ or graft rejection. Over recent years therehas been a considerable improvement in the efficiency of surgicaltechniques for transplanting tissues and organs such as skin, kidney,liver, heart, lung, pancreas and bone marrow. Perhaps the principaloutstanding problem is the lack of satisfactory agents for inducingimmunotolerance in the recipient to the transplanted allograft or organ.When allogeneic cells or organs are transplanted into a host (i.e., thedonor and donee are different individuals from the same species), thehost immune system is likely to mount an immune response to foreignantigens in the transplant (host-versus-graft disease) leading todestruction of the transplanted tissue.

In another aspect, the invention is a method for diagnosing whether anindividual has cancer, comprising determining whether there isexpression of KID31 on selected cells from the individual, wherein theexpression of KID31 on said cells is indicative of said cancer. In someembodiments, the expression of KID31 is determined using an anti-KID31antibody. In some embodiments, the method involves detecting the levelof KID31 expression from cells. The term “detection” as used hereinincludes qualitative and/or quantitative detection (measuring levels)with or without reference to a control.

In yet another aspect, the invention is a method of diagnosing cancer inan individual by detecting KID31 on or released from cells from theindividual, wherein the cancer is selected from the group including butnot limited to adrenal gland tumors, AIDS-associated cancers, alveolarsoft part sarcoma, astrocytic tumors, bladder cancer (squamous cellcarcinoma and transitional cell carcinoma), bone cancer (adamantinoma,aneurismal bone cysts, osteochondroma, osteosarcoma), brain and spinalcord cancers, metastatic brain tumors, breast cancer, carotid bodytumors, cervical cancer, chondrosarcoma, dhordoma, chromophobe renalcell carcinoma, clear cell carcinoma, colon cancer, colorectal cancer,cutaneous benign fibrous histiocytomas, desmoplastic small round celltumors, ependymomas, Ewing's tumors, extraskeletal myxoidchondrosarcoma, fibrogenesis imperfecta ossium, fibrous dysplasia of thebone, gallbladder and bile duct cancers, gestational trophoblasticdisease, germ cell tumors, head and neck cancers, islet cell tumors,Kaposi's Sarcoma, kidney cancer (nephroblastoma, papillary renal cellcarcinoma), leukemias, lipoma/benign lipomatous tumors,liposarcoma/malignant lipomatous tumors, liver cancer (hepatoblastoma,hepatocellular carcinoma), lymphomas, lung cancer, medulloblastoma,melanoma, meningiomas, multiple endocrine neoplasia, multiple myeloma,myelodysplastic syndrome, neuroblastoma, neuroendocrine tumors, ovariancancer, pancreatic cancers, papillary thyroid carcinomas, parathyroidtumors, pediatric cancers, peripheral nerve sheath tumors,phaeochromocytoma, pituitary tumors, prostate cancer, posterious unvealmelanoma, rare hematologic disorders, renal metastatic cancer, rhabdoidtumor, rhabdomysarcoma, sarcomas, skin cancer, soft-tissue sarcomas,squamous cell cancer, stomach cancer, synovial sarcoma, testicularcancer, thymic carcinoma, thymoma, thyroid metastatic cancer, anduterine cancers (carcinoma of the cervix, endometrial carcinoma, andleiomyoma).

In another aspect, the invention is a method for aiding diagnosis ofcancer (such as but not limited to kidney, ovarian, lung, prostate,pancreatic, colon, or breast cancer) in an individual comprisingdetermining the expression of KID31 in a biological sample from theindividual. In some embodiments, the expression of KID31 is determinedusing an anti-KID31 antibody. In some embodiments, the method isdetecting the level of KID31 expression from cells. The KID31 releasedfrom the cancer may contribute to elevated levels of KID31 or a portionthereof, being detectable in body fluids (e.g., blood, salivary or gutmucinous secretions).

In yet another aspect, the invention is a method of treating cancer byadministering an effective amount of an antibody that binds to KID31sufficient to reduce growth of cancerous cells. In some embodiments, theantibody is an anti-KID31 antibody. In certain embodiments, thecancerous cells are selected from the group including but not limited toadrenal gland tumors, AIDS-associated cancers, alveolar soft partsarcoma, astrocytic tumors, bladder cancer (squamous cell carcinoma andtransitional cell carcinoma), bone cancer (adamantinoma, aneurismal bonecysts, osteochondroma, osteosarcoma), brain and spinal cord cancers,metastatic brain tumors, breast cancer, carotid body tumors, cervicalcancer, chondrosarcoma, dhordoma, chromophobe renal cell carcinoma,clear cell carcinoma, colon cancer, colorectal cancer, cutaneous benignfibrous histiocytomas, desmoplastic small round cell tumors,ependymomas, Ewing's tumors, extraskeletal myxoid chondrosarcoma,fibrogenesis imperfecta ossium, fibrous dysplasia of the bone,gallbladder and bile duct cancers, gestational trophoblastic disease,germ cell tumors, head and neck cancers, islet cell tumors, Kaposi'sSarcoma, kidney cancer (nephroblastoma, papillary renal cell carcinoma),leukemias, lipoma/benign lipomatous tumors, liposarcoma/malignantlipomatous tumors, liver cancer (hepatoblastoma, hepatocellularcarcinoma), lymphomas, lung cancer, medulloblastoma, melanoma,meningiomas, multiple endocrine neoplasia, multiple myeloma,myelodysplastic syndrome, neuroblastoma, neuroendocrine tumors, ovariancancer, pancreatic cancers, papillary thyroid carcinomas, parathyroidtumors, pediatric cancers, peripheral nerve sheath tumors,phaeochromocytoma, pituitary tumors, prostate cancer, posterious unvealmelanoma, rare hematologic disorders, renal metastatic cancer, rhabdoidtumor, rhabdomysarcoma, sarcomas, skin cancer, soft-tissue sarcomas,squamous cell cancer, stomach cancer, synovial sarcoma, testicularcancer, thymic carcinoma, thymoma, thyroid metastatic cancer, anduterine cancers (carcinoma of the cervix, endometrial carcinoma, andleiomyoma). In certain preferred embodiments, the cancerous cells areselected from the group of solid tumors including but not limited tobreast cancer, colon cancer, prostate cancer, lung cancer, sarcoma,renal metastatic cancer, thyroid metastatic cancer, and clear cellcarcinoma.

In yet another aspect, the invention is a method of delaying developmentof metastasis in an individual having cancer comprising administering aneffective amount of at least one of a family of antibodies that bindspecifically to KID31. In one embodiment, the antibody is an anti-KID31antibody. In another aspect, the invention is a method of inhibitinggrowth and/or proliferation of cancer cells in vitro or in an individualcomprising administering an effective amount of a composition comprisingan anti-KID31 antibody associated with (including linked to) achemotherapeutic agent to the cell culture or sample, or to theindividual.

In yet another aspect, the invention is a method of delivering atherapeutic agent to a cancerous cell in an individual by administeringto the individual an effective amount of at least one member of a familyof antibodies, which bind specifically to KID31. In other embodiments,an anti-KID31 antibody is delivered to an individual in combination with(including linked to) another therapeutic agent.

In some embodiments, the anti-KID31 antibody is a humanized antibodyderived from a named antibody herein (generally, but not necessarily,comprising one or more partial or intact CDRs of the antibody). In someembodiments, the anti-KID31 antibody is a human antibody with one ormore properties of the named antibody. In some embodiments, thechemotherapeutic agent (such as a toxin or a radioactive molecule) isdelivered into the cancer cells (is internalized). In some embodiments,the agent is saporin.

In another aspect, the invention is a method of treating cancer in anindividual comprising administering an effective amount of a compositioncomprising an anti-KID31 antibody associated with (including linked to)a chemotherapeutic agent to the individual.

The present invention further provides methods for modulating, either byenhancing or reducing, the association of KID31 with a cytoplasmicsignaling partner. The association of KID31 with a cytoplasmic signalingpartner can be impacted by contacting a KID31 molecule presenting on acell surface, with an agent that modulates the binding of the signalingpartner to KID31. Agents which block or reduce KID31 association withits binding and/or signaling partners can be used to modulate biologicaland pathological processes which are involved in KID31-mediatedinflammation or immune responses. Pathological processes involving thisaction include tumor-associated cell growth.

Agents can be tested for their ability to block, reduce, enhance orotherwise modulate the association of KID31 with a binding partner, suchas an anti-KID31 antibody. Specifically, an agent can be tested for theability to modulate such an interaction by incubating a peptidecomprising the KID31 interaction site (typically in its nativeconformation as it exists on intact living cells) with a binding partnerand a test agent, and determining whether the test agent reduces orenhances the binding of the binding partner to the KID31 peptide.

Agonists, antagonists, and other modulators of KID31 function areexpressly included within the scope of this invention. These agonists,antagonists and modulators are polypeptides that comprise one or more ofthe antigenic determinant sites in KID31, or comprise one or morefragments of such sites, variants of such sites, or peptidomimetics ofsuch sites. These agonistic, antagonistic, and KID31 modulatorycompounds are provided in linear or cyclized form, and optionallycomprise at least one amino acid residue that is not commonly found innature or at least one amide isostere. These compounds may beglycosylated. The agonists, antagonists, and other modulators of KID31function of this invention are desirably used in all of the embodimentsand methods described above with reference to antibodies.

Other aspects of this invention relate to the novel antigen identifiedand referred to herein as KID31. This antigen is suitable for use as animmunogen and for a variety of research, diagnostic and therapeuticpurposes.

In certain aspects, the invention is a method for aiding in thediagnosis of disease in an individual comprising the steps of (i)assaying for the presence of KID31 in a blood or tissue sample obtainedfrom an individual; (ii) detecting whether said sample has an increasedamount of a KID31 marker relative to a normal (non-diseased) blood ortissue sample; and (iii) correlating an increased amount of said markerto a positive diagnosis or correlating the absence of an increasedamount of said marker to a negative diagnosis for disease. In certainembodiments, the marker is detected using an anti-KID31 antibody. Incertain embodiments, the method is effected by a technique selected fromthe group consisting of radionuclide imaging, flow cytometry, andimmunohistochemistry.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the graphed results of in vivo activity of mu-anti-KID31 onsub-renal tumor model using H322M cell line and Caki-2 cell line.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides a known antigen, carboxypeptidase M, referred toherein as KID31, which is expressed on cancerous cells of various tissuetypes, including but not limited to lung, kidney, pancreatic, ovarian,and colon cancers. Further, the invention provides monoclonal antibodiesand polypeptides that bind to KID31 and methods making and using theseantibodies and polypeptides to diagnose and treat various diseases humancancers associated with expression and/or over-expression of KID31.

I. General Techniques

The practice of the present invention will employ, unless otherwiseindicated, conventional techniques of molecular biology (includingrecombinant techniques), microbiology, cell biology, biochemistry andimmunology, which are within the skill of the art. Such techniques areexplained fully in the literature, such as, Molecular Cloning: ALaboratory Manual, second edition (Sambrook et al., 1989) Cold SpringHarbor Press; Oligonucleotide Synthesis (M. J. Gait, ed., 1984); Methodsin Molecular Biology, Humana Press; Cell Biology: A Laboratory Notebook(J. E. Cellis, ed., 1998) Academic Press; Animal Cell Culture (R. I.Freshney, ed., 1987); Introduction to Cell and Tissue Culture (J. P.Mather and P. E. Roberts, 1998) Plenum Press; Cell and Tissue Culture:Laboratory Procedures (A. Doyle, J. B. Griffiths, and D. G. Newell,eds., 1993-8) J. Wiley and Sons; Methods in Enzymology (Academic Press,Inc.); Handbook of Experimental Immunology (D. M. Weir and C. C.Blackwell, eds.); Gene Transfer Vectors for Mammalian Cells (J. M.Miller and M. P. Calos, eds., 1987); Current Protocols in MolecularBiology (F. M. Ausubel et al., eds., 1987); PCR: The Polymerase ChainReaction, (Mullis et al., eds., 1994); Current Protocols in Immunology(J. E. Coligan et al., eds., 1991); Short Protocols in Molecular Biology(Wiley and Sons, 1999); Immunobiology (C. A. Janeway and P. Travers,1997); Antibodies (P. Finch, 1997); Antibodies: a practical approach (D.Catty., ed., IRL Press, 1988-1989); Monoclonal antibodies: a practicalapproach (P. Shepherd and C. Dean, eds., Oxford University Press, 2000);Using antibodies: a laboratory manual (E. Harlow and D. Lane (ColdSpring Harbor Laboratory Press, 1999); The Antibodies (M. Zanetti and J.D. Capra, eds., Harwood Academic Publishers, 1995); and Cancer:Principles and Practice of Oncology (V. T. DeVita et al., eds., J. B.Lippincott Company, 1993).

II. Definitions

“KID31” refers to that polypeptide antigen, carboxypeptidase M, with amolecular weight of approximately 60 kDa to 80 kDa against which theantibodies of the present invention are directed. The KID31 is a cellsurface protein bound by anti-KID31 antibodies and present on skin andpancreatic ducts and several types of carcinomas. This antigen may havemore than one different epitope. It is currently believed that KID31 maybe over-expressed in certain cancer cells in comparison to their normaltissue counterparts.

Agonists, antagonists, and other modulators of function are expresslyincluded within the scope of this invention. These agonists, antagonistsand modulators are polypeptides that comprise one or more of theantigenic determinant sites in KID31, or comprise one or more fragmentsof such sites, variants of such sites, or peptidomimetics of such sites.These agonistic, antagonistic, and KID31 modulatory compounds areprovided in linear or cyclized form, and optionally comprise at leastone amino acid residue that is not commonly found in nature or at leastone amide isostere. These compounds may be glycosylated.

More specifically, the terms “KID31 modulator” as used herein aredefined as any compound that (1) is capable of disrupting or blockingthe interaction between human KID31 and its native ligands or ananti-KID31 antibody; (2) is capable of binding to human KID31 and itsnative ligands or an anti-KID31 antibody; (3) contains an antigenic sitethat can be used in the raising of antibodies capable of binding tohuman KID31 and its native ligands or an anti-KID31 antibody; (4)contains an antigenic site that can be used in the screening ofantibodies capable of binding to human KID31 and its native ligands oran anti-KID31 antibody; (5) contains an antigenic site that an be usedin the raising of antibodies capable of disrupting or blocking theinteraction between human KID31 and its native ligands or an anti-KID31antibody; (6) contains an antigenic site that can be used in thescreening of antibodies capable of disrupting or blocking theinteraction between human KID31 and its native ligands or an anti-KID31antibody. KID31 modulators may be “KID31 agonists” or “KID31antagonists” depending on whether their activity enhances or inhibitsnormal KID31 biological activity, respectively.

KID31 agonists, antagonists and modulators include KID31 variants, KID31peptide antagonists, peptidomimetics, and small molecules, anti-KID31antibodies and immunoglobulin variants, amino acid variants of humanKID31 including amino acid substitution, deletion, and additionvariants, or any combination thereof, and chimeric immunoglobulins. TheKID31 agonists, antagonists and modulators of this invention are basedon the inventors' identification of the KID31 domains involved in thebinding of human KID31 to its native ligands or anti-KID31 antibodies.Thus, the invention provides KID31 agonists, antagonists and modulatorswith molecular structures that duplicate or mimic one or more of theanti-KID31 binding domains of human KID31.

As used herein, the term “KID31 variant” denotes any amino acid variantof human KID31, including amino acid substitution, deletion, andaddition variants, or any combination thereof. The definitionencompasses chimeric molecules such as human KID31/non-human chimerasand other hybrid molecules. Also included in the definition is anyfragment of a KID31 variant molecule that comprises the variant orhybrid region(s) of the molecule.

An “antibody” is an immunoglobulin molecule capable of specific bindingto a target, such as a carbohydrate, polynucleotide, lipid, polypeptide,etc., through at least one antigen recognition site, located in thevariable region of the immunoglobulin molecule. As used herein, the termencompasses not only intact polyclonal or monoclonal antibodies, butalso fragments thereof (such as Fab, Fab′, F(ab′)₂, Fv), single chain(ScFv), mutants thereof, naturally occurring variants, fusion proteinscomprising an antibody portion with an antigen recognition site of therequired specificity, humanized antibodies, chimeric antibodies, and anyother modified configuration of the immunoglobulin molecule thatcomprises an antigen recognition site of the required specificity.

A “monoclonal antibody” refers to a homogeneous antibody populationwherein the monoclonal antibody is comprised of amino acids (naturallyoccurring and non-naturally occurring) that are involved in theselective binding of an antigen. Monoclonal antibodies are highlyspecific, being directed against a single antigenic site. The term“monoclonal antibody” encompasses not only intact monoclonal antibodiesand full-length monoclonal antibodies, but also fragments thereof (suchas Fab, Fab′, F(ab′)₂, Fv), single chain (ScFv), mutants thereof, fusionproteins comprising an antibody portion, humanized monoclonalantibodies, chimeric monoclonal antibodies, and any other modifiedconfiguration of the immunoglobulin molecule that comprises an antigenrecognition site of the required specificity and the ability to bind toan antigen. It is not intended to be limited as regards to the source ofthe antibody or the manner in which it is made (e.g., by hybridoma,phage selection, recombinant expression, transgenic animals, etc.). Theterm includes whole immunoglobulins as well as the fragments etc.described above under the definition of “antibody”.

“Humanized” antibodies refer to a chimeric molecule, generally preparedusing recombinant techniques, having an antigen binding site derivedfrom an immunoglobulin from a non-human species and the remainingimmunoglobulin structure of the molecule based upon the structure and/orsequence of a human immunoglobulin. The antigen-binding site maycomprise either complete variable domains fused onto constant domains oronly the complementarity determining regions (CDRs) grafted ontoappropriate framework regions in the variable domains. Antigen bindingsites may be wild type or modified by one or more amino acidsubstitutions. This eliminates the constant region as an immunogen inhuman individuals, but the possibility of an immune response to theforeign variable region remains (LoBuglio, A. F. et al., (1989) ProcNatl Acad Sci USA 86:4220-4224). Another approach focuses not only onproviding human-derived constant regions, but modifying the variableregions as well so as to reshape them as closely as possible to humanform. It is known that the variable regions of both heavy and lightchains contain three complementarity-determining regions (CDRs) whichvary in response to the antigens in question and determine bindingcapability, flanked by four framework regions (FRs) which are relativelyconserved in a given species and which putatively provide a scaffoldingfor the CDRs. When nonhuman antibodies are prepared with respect to aparticular antigen, the variable regions can be “reshaped” or“humanized” by grafting CDRs derived from nonhuman antibody on the FRspresent in the human antibody to be modified. Application of thisapproach to various antibodies has been reported by Sato, K., et al.,(1993) Cancer Res 53:851-856. Riechmann, L., et al., (1988) Nature332:323-327; Verhoeyen, M., et al., (1988) Science 239:1534-1536;Kettleborough, C. A., et al., (1991) Protein Engineering 4:773-3783;Maeda, H., et al., (1991) Human Antibodies Hybridoma 2:124-134; Gorman,S. D., et al., (1991) Proc Natl Acad Sci USA 88:4181-4185; Tempest, P.R., et al., (1991) Bio/Technology 9:266-271; Co, M. S., et al., (1991)Proc Natl Acad Sci USA 88:2869-2873; Carter, P., et al., (1992) ProcNatl Acad Sci USA 89:4285-4289; and Co, M. S. et al., (1992) J Immunol148:1149-1154. In some embodiments, humanized antibodies preserve allCDR sequences (for example, a humanized mouse antibody which containsall six CDRs from the mouse antibodies). In other embodiments, humanizedantibodies have one or more CDRs (one, two, three, four, five, six)which are altered with respect to the original antibody, which are alsotermed one or more CDRs “derived from” one or more CDRs from theoriginal antibody.

An epitope that “specifically binds” or “preferentially binds” (usedinterchangeably herein) to an antibody or a polypeptide is a term wellunderstood in the art, and methods to determine such specific orpreferential binding are also well known in the art. A molecule is saidto exhibit “specific binding” or “preferential binding” if it reacts orassociates more frequently, more rapidly, with greater duration and/orwith greater affinity with a particular cell or substance than it doeswith alternative cells or substances. An antibody “specifically binds”or “preferentially binds” to a target if it binds with greater affinity,avidity, more readily, and/or with greater duration than it binds toother substances. For example, an antibody that specifically orpreferentially binds to a KID31 epitope is an antibody that binds thisKID31 epitope with greater affinity, avidity, more readily, and/or withgreater duration than it binds to other KID31 epitopes or non-KID31epitopes. It is also understood by reading this definition that, forexample, an antibody (or moiety or epitope) that specifically orpreferentially binds to a first target may or may not specifically orpreferentially bind to a second target. As such, “specific binding” or“preferential binding” does not necessarily require (although it caninclude) exclusive binding. Generally, but not necessarily, reference tobinding means preferential binding.

The term “immunologically active” in reference to an epitope being or“remaining immunologically active” refers to the ability of an antibody(e.g., anti-KID31 antibody) to bind to the epitope under differentconditions, for example, after the epitope has been subjected toreducing and denaturing conditions.

Different biological functions are associated with anti-KID31antibodies, including, but not limited to, ability to bind to KID31(including KID31 on cancer cells, including but not limited to lung,kidney, pancreatic, ovarian, and colon cancer cells); ability to bind toa portion of KID31 that is exposed on the surface of a living cell invitro or in vivo; ability to deliver a chemotherapeutic agent tocancerous cells (such as lung, kidney, pancreatic, ovarian, and coloncancer cells) expressing KID31; ability to deliver a therapeutic agentor detectable marker into cancer cells expressing KID31. As discussedherein, polypeptides (including antibodies) of the invention may haveany one or more of these characteristics.

An “anti-KID31 equivalent antibody” or “anti-KID31 equivalentpolypeptide” refers to an antibody or a polypeptide having one or morebiological functions associated with an anti-KID31 antibody, such as,for example binding specificity.

As used herein, “agent” refers to a biological, pharmaceutical, orchemical compound. Non-limiting examples include simple or complexorganic or inorganic molecule, a peptide, a protein, an oligonucleotide,an antibody, an antibody derivative, antibody fragment, a vitaminderivative, a carbohydrate, a toxin, or a chemotherapeutic compound.Various compounds can be synthesized, for example, small molecules andoligomers (e.g., oligopeptides and oligonucleotides), and syntheticorganic compounds based on various core structures. In addition, variousnatural sources can provide compounds for screening, such as plant oranimal extracts, and the like. A skilled artisan can readily recognizethat there is no limit as to the structural nature of the agents of thepresent invention.

Agents that are employed in the methods of this invention can berandomly selected or rationally selected or designed. As used herein, anagent is said to be randomly selected when the agent is chosen randomlywithout considering the specific sequences involved in the associationof KID31 with its native binding partners or known antibodies. Anexample of randomly selected agents is the use of a chemical library ora peptide combinatorial library.

As used herein, an agent is said to be rationally selected or designedwhen the agent is chosen on a nonrandom basis that takes into accountthe sequence of the target site and/or its conformation in connectionwith the agent's action. With respect to anti-KID31 agents, it iscurrently believed that there are at least three epitopes on KID31against which antibodies can be raised and therefore at least threesites of action for agents that block KID31/anti-KID31 interaction. Thisinvention also encompasses agents that act at the sites of interactionbetween KID31 and its native binding partner, although other ligands andtheir active KID31-interactive sites are also encompassed within thescope of this invention, whether currently known or later identified.Agents can be rationally selected or rationally designed by utilizingthe peptide sequences that make up the contact sites of thereceptor/ligand and/or KID31/anti-KID31 antibody complex. For example, arationally selected peptide agent can be a peptide whose amino acidsequence is identical to an epitope appearing on KID31 as it is exposedon the surface of a living cell in its native environment. Such an agentwill reduce or block the association of the anti-KID31 antibody withKID31, or the association of KID31 with its native ligand, as desired,by binding to the anti-KID31 antibody or to the native ligand.

As used herein, the term “labeled”, with regard to the antibody, isintended to encompass direct labeling of the antibody by coupling (i.e.,physically linking) a detectable substance, such as a radioactive agentor a fluorophore (e.g. fluorescein isothiocyanate (FITC) orphycoerythrin (PE)) to the antibody, as well as indirect labeling of theprobe or antibody by reactivity with a detectable substance.

As used herein, the term “association”, with regard to the antibody,includes covalent and non-covalent attachment or binding to an agent(e.g., chemotherapeutic agent). The antibody can be associated with anagent (e.g., chemotherapeutic agent) by direct binding or indirectbinding via attachment to a common platform, such that the antibodydirects the localization of the agent to the cancerous cell to which theantibody binds and wherein the antibody and agent do not substantiallydissociate under physiological conditions such that the agent is nottargeted to the same cancerous cell to which the antibody binds or suchthat the agent's potency is not decreased.

A “biological sample” encompasses a variety of sample types obtainedfrom an individual and can be used in a diagnostic or monitoring assay.The definition encompasses saliva, blood and other liquid samples ofbiological origin, solid tissue samples such as a biopsy specimen ortissue cultures or cells derived therefrom, and the progeny thereof, forexample, cells obtained from a tissue sample collected from anindividual suspected of having cancer, in preferred embodiments fromovary, lung, prostate, pancreas, colon, and breast tissue. Thedefinition also includes samples that have been manipulated in any wayafter their procurement, such as by treatment with reagents,solubilization, or enrichment for certain components, such as proteinsor polynucleotides, or embedding in a semi-solid or solid matrix forsectioning purposes. The term “biological sample” encompasses a clinicalsample, and also includes cells in culture, cell supernatants, celllysates, serum, plasma, biological fluid, and tissue samples.

A “host cell” includes an individual cell or cell culture that can be orhas been a recipient for vector(s) for incorporation of polynucleotideinserts. Host cells include progeny of a single host cell, and theprogeny may not necessarily be completely identical (in morphology or ingenomic DNA complement) to the original parent cell due to natural,accidental, or deliberate mutation. A host cell includes cellstransfected in vivo with a polynucleotide(s) of this invention.

As used herein, “delaying development of metastasis” means to defer,hinder, slow, retard, stabilize, and/or postpone development ofmetastasis. This delay can be of varying lengths of time, depending onthe history of the cancer and/or individual being treated. As is evidentto one skilled in the art, a sufficient or significant delay can, ineffect, encompass prevention, in that the individual does not developthe metastasis.

An “effective amount” of a pharmaceutical composition, in oneembodiment, is an amount sufficient to effect beneficial or desiredresults including, without limitation, clinical results such asshrinking the size of the tumor (in the cancer context, for example,breast or prostate cancer), retardation of cancerous cell growth,delaying the development of metastasis, decreasing symptoms resultingfrom the disease, increasing the quality of life of those suffering fromthe disease, decreasing the dose of other medications required to treatthe disease, enhancing the effect of another medication such as viatargeting and/or internalization, delaying the progression of thedisease, and/or prolonging survival of individuals. An effective amountcan be administered in one or more administrations. For purposes of thisinvention, an effective amount of drug, compound, or pharmaceuticalcomposition is an amount sufficient to reduce the proliferation of (ordestroy) cancerous cells and to reduce and/or delay the development, orgrowth, of metastases of cancerous cells, either directly or indirectly.In some embodiments, an effective amount of a drug, compound, orpharmaceutical composition may or may not be achieved in conjunctionwith another drug, compound, or pharmaceutical composition. Thus, an“effective amount” may be considered in the context of administering oneor more chemotherapeutic agents, and a single agent may be considered tobe given in an effective amount if, in conjunction with one or moreother agents, a desirable result may be or is achieved. While individualneeds vary, determination of optimal ranges of effective amounts of eachcomponent is within the skill of the art. Typical dosages comprise 0.1-to 100 mg/kg/body weight. The preferred dosages comprise 1- to100-mg/kg/body weight. The most preferred dosages comprise 10- to100-mg/kg/body weight.

As used herein, a nucleic acid molecule or agent, antibody, compositionor cell, etc., is said to be “isolated” when that nucleic acid molecule,agent, antibody, composition, or cell, etc. is substantially separatedfrom contaminant nucleic acid molecules, antibodies, agents,compositions, or cells, etc. from its original source.

An “individual” is a vertebrate, preferably a mammal, more preferably ahuman. Mammals include, but are not limited to, farm animals, sportanimals, pets, primates, mice and rats.

The terms “polypeptide”, “oligopeptide”, “peptide” and “protein” areused interchangeably herein to refer to polymers of amino acids of anylength. The polymer may be linear or branched, it may comprise modifiedamino acids, and it may be interrupted by non-amino acids. The termsalso encompass an amino acid polymer that has been modified naturally orby intervention; for example, disulfide bond formation, glycosylation,lipidation, acetylation, phosphorylation, or any other manipulation ormodification, such as conjugation with a labeling component. Alsoincluded within the definition are, for example, polypeptides containingone or more analogs of an amino acid (including, for example, unnaturalamino acids, etc.), as well as other modifications known in the art. Itis understood that, because the polypeptides of this invention are basedupon an antibody, the polypeptides can occur as single chains orassociated chains.

Also encompassed within the scope of the invention are peptidomimeticsof the KID31 peptide agonists, antagonists and modulators (includinganti-KID31 antibodies) described herein. Such peptidomimetics includepeptides wherein at least one amino acid residue is substituted with anamino acid residue that is not commonly found in nature, such as the Disomer of the amino acid or an N-alkylated species of the amino acid. Inother embodiments, peptidomimetics are constructed by replacing at leastone amide bond (—C(.dbd.O)—NH—) in a KID31 peptide agonist, antagonistor modulators with an amide isostere. Suitable amide isosteres include—CH.sub.2—NH—, —CH.sub.2—S—, —CH.sub.2—S(O).sub.n—(where n is 1 or 2),—CH.sub.2—CH.sub.2—, —CH.dbd.CH—(E or Z), —C(.dbd.O)—CH.sub.2—,—CH(CN)—NH—, —C(OH)—CH.sub.2—, and —O—C(.dbd.O)—NH—. The amide bonds ina KID31 peptide agonist, antagonist or modulator that are suitablecandidates for replacement with amide isosteres include bonds that arehydrolyzable by the endogenous esterases or proteases of the intendedsubject of KID31 peptide agonist, antagonist or modulator treatment.

As used herein, “substantially pure” refers to material that is at least50% pure (i.e., free from contaminants), more preferably at least 90%pure, more preferably at least 95% pure, more preferably at least 98%pure, more preferably at least 99% pure, or greater, pure.

“Toxin” refers to any substance, which effects an adverse responsewithin a cell. For example, a toxin directed to a cancerous cell wouldhave an adverse, sometimes deleterious effect, on the cancerous cell.Examples of toxins include, but are not limited to, radioisotopes,calicheamicin, and maytansinoids.

As used herein, “treatment” or “treating” is an approach for obtainingbeneficial or desired results including and preferably clinical results.For purposes of this invention, beneficial or desired clinical resultsinclude, but are not limited to, one or more of the following: reducingthe proliferation of (or destroying) cancerous cells or other diseased,reducing metastasis of cancerous cells found in cancers, shrinking thesize of the tumor, decreasing symptoms resulting from the disease,increasing the quality of life of those suffering from the disease,decreasing the dose of other medications required to treat the disease,delaying the progression of the disease, and/or prolonging survival ofindividuals.

III. Methods of Making Antibodies and Polypeptides

Methods of making monoclonal antibodies are known in the art. One methodwhich may be employed is the method of Kohler and Milstein, Nature256:495-497 (1975) or a modification thereof. Typically, monoclonalantibodies are developed in non-human species, such as mice. In general,a mouse or rat is used for immunization but other animals may also beused. The antibodies are produced by immunizing mice with an immunogenicamount of cells, cell extracts, or protein preparations that containhuman KID31. The immunogen can be, but is not limited to, primary cells,cultured cell lines, cancerous cells, nucleic acids, or tissue. In oneembodiment, human fetal kidney epithelial cells are used. In anotherembodiment, human bladder or pancreatic progenitor cells are used.Methods for isolating and culturing human fetal kidney cells aredetailed in Example 1. Cells used for immunization, for example, humanfetal kidney, bladder cells or human pancreatic progenitor cells, may becultured for a period of time (at least 24 hours) prior to their use asan immunogen. Cells (e.g., human fetal kidney, bladder cells or humanpancreatic progenitor cells) may be used as immunogens by themselves orin combination with a non-denaturing adjuvant, such as Ribi. In general,cells should be kept intact and preferably viable when used asimmunogens. Intact cells may allow antigens to be better detected thanruptured cells by the immunized animal. Use of denaturing or harshadjuvants, e.g., Freud's adjuvant, may rupture the human fetal kidney orother cells and therefore is discouraged. The immunogen may beadministered multiple times at periodic intervals such as, bi-weekly, orweekly, or may be administered in such a way as to maintain viability inthe animal (e.g., in a tissue recombinant). Example 2 describes methodsused to generate anti-KID31 antibodies and may be used to generate othermonoclonal antibodies, which bind to KID31.

In one embodiment, monoclonal antibodies, which bind to KID31 areobtained by using host cells that over-express KID31 as an immunogen.Such cells include, by way of example and not by limitation, human fetalkidney cells and human lung cancer cells.

To monitor the antibody response, a small biological sample (e.g.,blood) may be obtained from the animal and tested for antibody titeragainst the immunogen. The spleen and/or several large lymph nodes canbe removed and dissociated into single cells. If desired, the spleencells may be screened (after removal of non-specifically adherent cells)by applying a cell suspension to a plate or to a well coated with theantigen. B-cells, expressing membrane-bound immunoglobulin specific forthe antigen, will bind to the plate, and are not rinsed away with therest of the suspension. Resulting B-cells, or all dissociated spleencells, can then be fused with myeloma cells (e.g., X63-Ag8.653 and thosefrom the Salk Institute, Cell Distribution Center, San Diego, Calif.).Polyethylene glycol (PEG) may be used to fuse spleen or lymphocytes withmyeloma cells to form a hybridoma. The hybridoma is then cultured in aselective medium (e.g., hypoxanthine, aminopterin, thymidine medium,otherwise known as “HAT medium”). The resulting hybridomas are thenplated by limiting dilution, and are assayed for the production ofantibodies that bind specifically to the immunogen (e.g., surface of thehuman fetal kidney cells, surface of cancer cell lines, Ag-KID31, fetalbladder sections, etc.) using FACS or immunohistochemistry (IHCscreening). The selected monoclonal antibody-secreting hybridomas arethen cultured either in vitro (e.g., in tissue culture bottles or hollowfiber reactors), or in vivo (e.g., as ascites in mice). Examples 2 and 3provides further details about the methods utilized to obtain, purifyand screen an anti-KID31 antibody.

As another alternative to the cell fusion technique, EBV immortalized Bcells may be used to produce monoclonal antibodies of the subjectinvention. The hybridomas are expanded and subcloned, if desired, andsupernatants are assayed for anti-immunogen activity by conventionalassay procedures (e.g., FACS, IHC, radioimmunoassay, enzyme immunoassay,fluorescence immunoassay, etc.).

In another alternative, monoclonal antibody anti-KID31 and any otherequivalent antibodies can be sequenced and produced recombinantly by anymeans known in the art (e.g., humanization, use of transgenic mice toproduce fully human antibodies, phage display technology, etc.). In oneembodiment, anti-KID31 monoclonal antibody is sequenced and thepolynucleotide sequence is then cloned into a vector for expression orpropagation. The sequence encoding the antibody of interest may bemaintained in a vector in a host cell and the host cell can then beexpanded and frozen for future use.

The polynucleotide sequence of monoclonal antibody anti-KID31 and anyother equivalent antibodies may be used for genetic manipulation togenerate a “humanized” antibody, to improve the affinity, or othercharacteristics of the antibody. The general principle in humanizing anantibody involves retaining the basic sequence of the antigen-bindingportion of the antibody, while swapping the non-human remainder of theantibody with human antibody sequences. There are four general steps tohumanize a monoclonal antibody. These are: (1) determining thenucleotide and predicted amino acid sequence of the starting antibodylight and heavy variable domains (2) designing the humanized antibody,i.e., deciding which antibody framework region to use during thehumanizing process (3) the actual humanizing methodologies/techniquesand (4) the transfection and expression of the humanized antibody. See,for example, U.S. Pat. Nos. 4,816,567; 5,807,715; 5,866,692; and6,331,415.

A number of “humanized” antibody molecules comprising an antigen-bindingsite derived from a non-human immunoglobulin have been described,including chimeric antibodies having rodent or modified rodent V regionsand their associated complementarity determining regions (CDRs) fused tohuman constant domains. See, for example, Winter et al. Nature349:293-299 (1991), Lobuglio et al. Proc. Nat. Acad. Sci. USA86:4220-4224 (1989), Shaw et al. J Immunol. 138:4534-4538 (1987), andBrown et al. Cancer Res. 47:3577-3583 (1987). Other references describerodent CDRs grafted into a human supporting framework region (FR) priorto fusion with an appropriate human antibody constant domain. See, forexample, Riechmann et al. Nature 332:323-327 (1988), Verhoeyen et al.Science 239:1534-1536 (1988), and Jones et al. Nature 321:522-525(1986). Another reference describes rodent CDRs supported byrecombinantly veneered rodent framework regions. See, for example,European Patent Publication No. 519,596. These “humanized” molecules aredesigned to minimize unwanted immunological response toward rodentanti-human antibody molecules, which limits the duration andeffectiveness of therapeutic applications of those moieties in humanrecipients. Other methods of humanizing antibodies that may also beutilized are disclosed by Daugherty et al., Nucl. Acids Res.,19:2471-2476 (1991) and in U.S. Pat. Nos. 6,180,377; 6,054,297;5,997,867; and 5,866,692.

The invention also encompasses single chain variable region fragments(“scFv”) of antibodies of this invention, such as mu-anti-KID31. Singlechain variable region fragments are made by linking light and/or heavychain variable regions by using a short linking peptide. Bird et al.(1988) Science 242: 423-426 describes example of linking peptides whichbridge approximately 3.5 nm between the carboxy terminus of one variableregion and the amino terminus of the other variable region. Linkers ofother sequences have been designed and used, Bird et al. (1988). Linkerscan in turn be modified for additional functions, such as attachment ofdrugs or attachment to solid supports. The single chain variants can beproduced either recombinantly or synthetically. For synthetic productionof scFv, an automated synthesizer can be used. For recombinantproduction of scFv, a suitable plasmid containing polynucleotide thatencodes the scFv can be introduced into a suitable host cell, eithereukaryotic, such as yeast, plant, insect or mammalian cells, orprokaryotic, such as E. coli. Polynucleotides encoding the scFv ofinterest can be made by routine manipulations such as ligation ofpolynucleotides. The resultant scFv can be isolated using standardprotein purification techniques known in the art.

The invention includes modifications to KID31 agonists, antagonists,modulators and antibodies, including functionally equivalent antibodiesand polypeptides that do not significantly affect their properties andvariants that have enhanced or decreased activity. Modification ofpolypeptides is routine practice in the art and need not be described indetail herein. Examples of modified polypeptides include polypeptideswith conservative substitutions of amino acid residues, one or moredeletions or additions of amino acids which do not significantlydeleteriously change the functional activity, or use of chemicalanalogs. Amino acid residues which can be conservatively substituted forone another include but are not limited to: glycine/alanine;valine/isoleucine/leucine; asparagine/glutamine; aspartic acid/glutamicacid; serine threonine; lysine/arginine; and phenylalanine/tryosine.These polypeptides also include glycosylated and nonglycosylatedpolypeptides, as well as polypeptides with other post-translationalmodifications, such as, for example, glycosylation with differentsugars, acetylation, and phosphorylation. Preferably, the amino acidsubstitutions would be conservative, i.e., the substituted amino acidwould possess similar chemical properties as that of the original aminoacid. Such conservative substitutions are known in the art, and exampleshave been provided above. Amino acid modifications can range fromchanging or modifying one or more amino acids to complete redesign of aregion, such as the variable region. Changes in the variable region canalter binding affinity and/or specificity. Other methods of modificationinclude using coupling techniques known in the art, including, but notlimited to, enzymatic means, oxidative substitution and chelation.Modifications can be used, for example, for attachment of labels forimmunoassay, such as the attachment of radioactive moieties forradioimmunoassay. Modified polypeptides are made using establishedprocedures in the art and can be screened using standard assays known inthe art.

The invention also encompasses fusion proteins comprising one or morefragments or regions from the polypeptides and antibodies of thisinvention. In one embodiment, a fusion polypeptide is provided thatcomprises at least 10 contiguous amino acids of variable light chainregion and at least 10 amino acids of variable heavy chain region. Inanother embodiment, the fusion polypeptide contains a heterologousimmunoglobulin constant region. In another embodiment, the fusionpolypeptide contains a light chain variable region and a heavy chainvariable region of an antibody produced from a hybridoma deposited withthe ATCC as described herein. For purposes of this invention, anantibody fusion protein contains one or more anti-KID31 polypeptides andanother amino acid sequence to which it is not attached in the nativemolecule, for example, a heterologous sequence or a homologous sequencefrom another region.

An anti-KID31 polypeptide, and other KID31 agonists, antagonists andmodulators can be created by methods known in the art, for example,synthetically or recombinantly. One method of producing KID31 peptideagonists, antagonists and modulators involves chemical synthesis of thepolypeptide, followed by treatment under oxidizing conditionsappropriate to obtain the native conformation, that is, the correctdisulfide bond linkages. This can be accomplished using methodologieswell known to those skilled in the art (see Kelley, R. F. & Winkler, M.E. in Genetic Engineering Principles and Methods, Setlow, J. K., ed.,Plenum Press, N.Y., vol. 12, pp 1-19 (1990); Stewart, J. M. & Young, J.D. Solid Phase Peptide Synthesis Pierce Chemical Co. Rockford, Ill.(1984); see also U.S. Pat. Nos. 4,105,603; 3,972,859; 3,842,067; and3,862,925).

Polypeptides of the invention may be conveniently prepared using solidphase peptide synthesis (Merrifield, J. Am. Chem. Soc., 85:2149 (1964);Houghten, Proc. Natl. Acad. Sci. USA 82:5132 (1985)).

In yet another alternative, fully human antibodies may be obtained byusing commercially available mice that have been engineered to expressspecific human immunoglobulin proteins. Transgenic animals that aredesigned to produce a more desirable (e.g., fully human antibodies) ormore robust immune response may also be used for generation of humanizedor human antibodies. Examples of such technology are Xenomouse™ fromAbgenix, Inc. (Fremont, Calif.) and HuMAb-Mouse® and TC Mouse™ fromMedarex, Inc. (Princeton, N.J.).

In an alternative, antibodies may be made recombinantly and expressedusing any method known in the art. Antibodies may be made recombinantlyby first isolating the antibodies made from host animals, obtaining thegene sequence, and using the gene sequence to express the antibodyrecombinantly in host cells (e.g., CHO cells). Another method that maybe employed is to express the antibody sequence in plants (e.g.,tobacco) or transgenic milk. Methods for expressing antibodiesrecombinantly in plants or milk have been disclosed. See, for example,Peeters, et al. (2001) Vaccine 19:2756; Lonberg, N. and D. Huszar (1995)Int. Rev. Immunol 13:65; and Pollock, et al.(1999) J Immunol Methods231:147. Methods for making derivatives of antibodies, e.g., humanized,single chain, etc. are known in the art. In another alternative,antibodies may be made recombinantly by phage display technology. See,for example, U.S. Pat. Nos. 5,565,332; 5,580,717; 5,733,743; 6,265,150;and Winter et al., Annu. Rev. Immunol. 12:433-455 (1994).

The antibodies or protein of interest may be subjected to sequencing byEdman degradation, which is well known to those of skill in the art. Thepeptide information generated from mass spectrometry or Edmandegradation can be used to design probes or primers that are used toclone the protein of interest.

An alternative method of cloning the protein of interest is by “panning”using purified KID31 or portions thereof for cells expressing theantibody or protein of interest. The “panning” procedure is conducted byobtaining a cDNA library from tissues or cells that express the antibodyor protein of interest, over-expressing the cDNAs in a second cell type,and screening the transfected cells of the second cell type for aspecific binding to KID31. Detailed descriptions of the methods used incloning mammalian genes coding for cell surface proteins by “panning”can be found in the art. See, for example, Aruffo, A. and Seed, B. Proc.Natl. Acad. Sci. USA, 84, 8573-8577 (1987) and Stephan, J. et al.,Endocrinology 140: 5841-5854 (1999).

cDNAs encoding anti-KID31 antibodies, and other KID31 peptide agonists,antagonists and modulators can be obtained by reverse transcribing themRNAs from a particular cell type according to standard methods in theart. Specifically, mRNA can be isolated using various lytic enzymes orchemical solutions according to the procedures set forth in Sambrook, etal. supra or extracted by commercially available nucleic-acid-bindingresins following the accompanying instructions provided by manufacturers(e.g., Qiagen, Invitrogen, Promega). The synthesized cDNAs are thenintroduced into an expression vector to produce the antibody or proteinof interest in cells of a second type. It is implied that an expressionvector must be replicable in the host cells either as episomes or as anintegral part of the chromosomal DNA. Suitable expression vectorsinclude but are not limited to plasmids, viral vectors, includingadenoviruses, adeno-associated viruses, retroviruses, and cosmids.

The vectors containing the polynucleotides of interest can be introducedinto the host cell by any of a number of appropriate means, includingelectroporation, transfection employing calcium chloride, rubidiumchloride, calcium phosphate, DEAE-dextran, or other substances;microprojectile bombardment; lipofection; and infection (e.g., where thevector is an infectious agent such as vaccinia virus). The choice ofintroducing vectors or polynucleotides will often depend on features ofthe host cell.

Any host cells capable of over-expressing heterologous DNAs can be usedfor the purpose of isolating the genes encoding the antibody,polypeptide or protein of interest. Non-limiting examples of mammalianhost cells include but not limited to COS, HeLa, and CHO cells.Preferably, the host cells express the cDNAs at a level of about 5 foldhigher, more preferably 10 fold higher, even more preferably 20 foldhigher than that of the corresponding endogenous antibody or protein ofinterest, if present, in the host cells. Screening the host cells for aspecific binding to KID31 is effected by an immunoassay or FACS. A cellover-expressing the antibody or protein of interest can be identified.

Various techniques are also available which may now be employed toproduce mutant KID31 peptide agonists, antagonists, and modulators whichencodes for additions, deletions, or changes in amino acid sequence ofthe resultant protein relative to the parent KID31 peptide agonist,antagonist or modulator molecule.

The invention includes polypeptides comprising an amino acid sequence ofthe antibodies of this invention. The polypeptides of this invention canbe made by procedures known in the art. The polypeptides can be producedby proteolytic or other degradation of the antibodies, by recombinantmethods (i.e., single or fusion polypeptides) as described above or bychemical synthesis. Polypeptides of the antibodies, especially shorterpolypeptides up to about 50 amino acids, are conveniently made bychemical synthesis. Methods of chemical synthesis are known in the artand are commercially available. For example, an anti-KID31 polypeptidecould be produced by an automated polypeptide synthesizer employing thesolid phase method.

IV. Methods for Screening Polypeptides and Monoclonal Antibodies

Several methods may be used to screen polypeptides and monoclonalantibodies that bind to KID31. It is understood that “binding” refers tobiologically or immunologically relevant binding, i.e., binding which isspecific for the unique antigen for which the immunoglobulin molecule isencoded, or to which the polypeptide is directed. It does not refer tonon-specific binding that may occur when an immunoglobulin is used at avery high concentration against a non-specific target. In oneembodiment, monoclonal antibodies are screened for binding to KID31using standard screening techniques. In this manner, anti-KID31monoclonal antibody was obtained. In accordance with the BudapestTreaty, a hybridoma which produces anti-KID31 monoclonal antibodies hasbeen deposited in the American Type Culture Collection (ATCC) 10801University Blvd., Manassas Va. 20110-2209 on Mar. 20, 2003 with a PatentDeposit Designation of PTA# 6516.

Monoclonal antibodies that bind to KID31 are screened for binding tocancerous tissues and non-cancerous cells. In one embodiment, monoclonalantibodies which bind to KID31 and that are also cross reactive to humancancerous cells or tissues, but not to normal cells or tissues to thesame degree, are selected. One method that may be employed for screeningis immunohistochemistry (IHC). Standard immunohistochemical techniquesare known to those of average skill in the art. See, for example, AnimalCell Culture Methods (J. P. Mather and D. Barnes, eds., Academic Press,Vol. 57, Ch. 18 and 19, pp. 314-350, 1998). Biological samples (e.g.,tissues) may be obtained from biopsies, autopsies, or necropsies. Toascertain if KID31 is present only on cancerous cells, anti-KID31antibodies may be used to detect the presence of KID31 on tissues fromindividuals with cancer while other non-cancerous tissues from theindividual suffering from cancer or tissues from individuals withoutcancer are used as a control. The tissue can be embedded in a solid orsemi-solid substance that prevents damage during freezing (e.g., agarosegel or OCT) and then sectioned for staining. Cancers from differentorgans and at different grades can be used to screen monoclonalantibodies. Examples of tissues that may be used for screening purposesinclude but are not limited to ovary, breast, lung, prostate, colon,kidney, skin, thyroid, brain, heart, liver, stomach, nerve, bloodvessels, bone, upper digestive tract, and pancreas. Examples ofdifferent cancer types that may be used for screening purposes includebut are not limited to carcinomas, adenocarcinomas, sarcomas,adenosarcomas, lymphomas, and leukemias.

In yet another alternative, cancerous cells lines such as BT474 (ATCC #HTB-20), MCF7 (ATCC# HTB-22), ES-2 (ATCC# CRL-1978), SKOV3 (ATCC #HTB-77), SKMES-1 (ATCC# HTB-58), CA130 (Raven proprietary lungadenocarcinoma cell line), CaLu3 (ATCC# HTB-55), 9926 (Raven proprietarypancreas adenocarcinoma cell line, AsPC-1 (ATCC# CRL-1682), Hs700T(ATCC# HTB-147), Colo205 (ATCC# CCL-222), HT-29 (HTB-38), Cos7 (ATCC#CRL-1651), RL-65 (ATCC# CRL-10345), A204 (ATCC# HTB-82), G292 (ATCC#CRL-1423), HT1080 (ATCC# CCL-121), MG63 (ATCC# CRL-1427), RD (ATCC#CCL-136), RD-ES (ATCC# HTB-166), SKES-1 (ATCC# HTB-86), SKLMS-1 (ATCC#HTB-88), SKUT-1 (ATCC# HTB-114), SW684 (ATCC# HTB-91), SW872 (ATCC#HTB-92), 786-O (ATCC# CRL-1932), A498 (ATCC# HTB-44), Caki-2 (ATCC#HTB-47), 22RV1 (ATCC# CRL-2505), DU145 (ATCC# HTB-81), LNCaP (ATCC#CRL-1740), and normal cells from their respective tissues may be used toscreen for monoclonal antibodies which are specific for canceroustissue. Primary, or low passage, cell cultures derived from normaltissues from different organs, including but not limited to, kidney,ovary, breast, lung, prostate, colon, kidney, skin, thyroid, aorticsmooth muscle, and endothelial cells can be used as negative controls.The cancerous or non-cancerous cells can be grown on glass slides orcoverslips, or on plastic surfaces, or prepared in a CellArray™, asdescribed in WO 01/43869, and screened for the binding of antibody usingIHC as described above for tissues. Alternatively, cells may be removedfrom the growth surface using non-proteolytic means and spun into apellet, which is then embedded and treated as tissues for IHC analysisas described above. Cells may be inoculated into immunodeficientanimals, a tumor allowed to grow, and then this tumor may be harvested,embedded, and used as a tissue source for IHC analysis. In anotheralternative, single cells may be screened by incubating with the primaryantibody, a secondary “reporter” antibody linked to a fluorescentmolecule and then analyzed using a fluorescent activated cell-sorting(FACS) machine.

Several different detection systems may be utilized to detect binding ofantibodies to tissue section. Typically, immunohistochemistry involvesthe binding of a primary antibody to the tissue and then a secondaryantibody reactive against the species from the primary antibody wasgenerated and conjugated to a detectable marker (e.g., horseradishperoxidase, HRP, or diaminobenzedine, DAB). One alternative method thatmay be used is polyclonal mirror image complementary antibodies orpolyMICA. PolyMICA (polyclonal Mirror Image Complementary Antibodies)technique, described by D. C. Mangham and P. G. Isaacson (Histopathology(1999) 35(2):129-33), can be used to test binding of primary antibodies(e.g., anti-KID31 antibodies) to normal and cancerous tissue. Severalkinds of polyMICA™ Detection kits are commercially available from TheBinding Site Limited (P.O. Box 4073 Birmingham B29 6AT England). ProductNo. HK004.D is a polyMICA™ Detection kit which uses DAB chromagen.Product No. HK004.A is a polyMICA™ Detection kit which uses AECchromagen. Alternatively, the primary antibody may be directly labeledwith the detectable marker.

The first step in IHC screening to select for an appropriate antibody isthe binding of primary antibodies raised in mice (e.g., anti-KID31antibodies) to one or more immunogens (e.g., cells or tissue samples).In one embodiment, the tissue sample is sections of frozen tissue fromdifferent organs. The cells or tissue samples can be either cancerous ornon-cancerous.

Frozen tissues can be prepared, sectioned, with or without fixation, andIHC performed by any of a number of methods known to one familiar withthe art. See, for example, Stephan et al. Dev. Biol. 212: 264-277(1999), and Stephan et al. Endocrinology 140: 5841-54 (1999).

V. Methods of Characterizing Anti-KID31 Antibodies

Several methods can be used to characterize anti-KID31 antibodies. Onemethod is to identify the epitope to which it binds. Epitope mapping iscommercially available from various sources, for example, PepscanSystems (Edelhertweg 15, 8219 PH Lelystad, The Netherlands). Epitopemapping can be used to determine the sequence to which an anti-KID31antibody binds. The epitope can be a linear epitope, i.e., contained ina single stretch of amino acids, or a conformational epitope formed by athree-dimensional interaction of amino acids that may not necessarily becontained in a single stretch. Peptides of varying lengths (e.g., atleast 4-6 amino acids long) can be isolated or synthesized (e.g.,recombinantly) and used for binding assays with anti-KID31 antibody. Theepitope to which anti-KID31 antibody binds can be determined in asystematic screening by using overlapping peptides derived from theextracellular sequence and determining binding by anti-KID31 antibody.

Yet another method that can be used to characterize an anti-KID31antibody is to use competition assays with other antibodies known tobind to the same antigen, i.e., KID31 to determine if anti-KID31antibodies binds to the same epitope as other antibodies. Examples ofcommercially available antibodies to KID31 may be available and may beidentified using binding and competition assays that are well known inthe art. Anti-KID31 antibodies can be further characterized by thetissues, type of cancer or type of tumor to which they bind.

Another method of characterizing anti-KID31 antibodies is by the antigento which it binds. Anti-KID31 antibodies were used in Western blots withcell lysates from various human cancers. As is known to one of skill inthe art, Western blotting can involve running cell lysates and/or cellfractions on a denaturing or non-denaturing gel, transferring theproteins to nitrocellulose paper, and then probing the blot with anantibody (e.g., anti-KID31 antibody) to see which proteins are bound bythe antibody. Alternatively, proteins on the cell surface can bebiotinylated and anti-KID31 antibodies can be used to immunoprecipitatebiotinylated KID31. Biotinylated KID31 can then be visualized usingHRP-strepavidin. This procedure is detailed further in Example 4. KID31is associated with various human cancers of different tissues includingbut not limited to lung, kidney, pancreatic, ovarian, and colon. Furtherdescription of KID31 expression is given in Example 5 and 6.

VI. Methods of Diagnosing Cancer Using Anti-KID31 Antibodies and KID31Modulators

Monoclonal antibodies to KID31 made by the methods disclosed herein maybe used to identify the presence or absence of cancerous cells in avariety of tissues, including but not limited to, ovary, breast, lung,prostate, colon, kidney, pancreas, skin, thyroid, brain, heart, liver,stomach, nerve, blood vessels, bone, and upper digestive tract, forpurposes of diagnosis. Monoclonal antibodies to KID31 made by themethods disclosed herein may also be used to identify the presence orabsence of cancerous cells, or the level thereof, which are circulatingin blood after their release from a solid tumor. Such circulatingantigen may be an intact KID31 antigen, or a fragment thereof thatretains the ability to be detected according to the methods taughtherein. Such detection may be effected by FACS analysis using standardmethods commonly used in the art.

These uses can involve the formation of a complex between KID31 and anantibody that binds specifically to KID31. Examples of such antibodiesinclude but are not limited to those anti-KID31 monoclonal antibodiesproduced by the hybridoma deposited in the ATCC with the designationPTA# 6516. The formation of such a complex can be in vitro or in vivo.Without being bound by theory, monoclonal antibody anti-KID31 can bindto KID31 through the extracellular domain of KID31 and may then beinternalized.

In a preferred embodiment of the diagnostic methods of this invention,the antibody bears a detectable label. Examples of labels that may beused include a radioactive agent or a fluorophore, such asfluoroisothiocyanate or phycoerythrin.

As with other known antibodies used commercially for diagnostic andtherapeutic purposes, the target antigen of this invention is broadlyexpressed in normal tissue. It is also up regulated in some tumors.Therefore, the particular dosages and routes of delivery of theantibodies of this invention as used for diagnostic or therapeuticagents will be tailored to the particular tumor or disease state athand, as well as to the particular individual being treated.

One method of using the antibodies for diagnosis is in vivo tumorimaging by linking the antibody to a radioactive or radioopaque agent,administering the antibody to the individual and using an x-ray or otherimaging machine to visualize the localization of the labeled antibody atthe surface of cancer cells expressing the antigen. The antibody isadministered at a concentration that promotes binding at physiologicalconditions.

In vitro techniques for detection of KID31 are routine in the art andinclude enzyme linked immunosorbent assays (ELISAs),immunoprecipitations, immunofluorescence, enzyme immunoassay (EIA),radioimmunoassay (RIA), and Western blot analysis.

In aspects of this invention, methods of radioimaging of tumours orneoplasms, or of measuring the effectiveness of a method of treatmentwith a radiolabelled antibody, comprising the step of administering aradiolabelled, tumour-specific antibody to an individual following thepractice of this invention. The radiolabelled antibody may be amonoclonal or polyclonal antibody comprising a radiolabel, preferablyselected from the group consisting of Technetium-99m, Indium-111,Iodine-131, Rhenium-186, Rhenium-188, Samarium-153, Lutetium-177,Copper-64, Scandium-47, Yttrium-90. Monoclonal antibodies labelled withtherapeutic radionuclides such as Iodine-131, Rhenium-188, Holmium-166,Samarium-153 and Scandium-47, which do not compromise theimmunoreactivity of antibodies and are not broken down in vivo, areespecially preferred. The person skilled in the art will appreciate thatother radioactive isotopes are known, and may be suitable for specificapplications. The radioimaging may be conducted using Single PhotonEmission Computer Tomography (SPECT), Position Emmission Tomography(PET), Computer Tomography (CT) or Magnetic Resonance Imaging (MRI).Correlative imaging, which permits greater anatomical definition oflocation of metastases located by radioimmunoimaging, is alsocontemplated.

In other methods, the cancerous cells are removed and the tissueprepared for immunohistochemistry by methods well known in the art(e.g., embedding in a freezing compound, freezing and sectioning, withor without fixation; fixation and paraffin embedding with or withoutvarious methods of antigen retrieval and counterstaining). Themonoclonal antibodies may also be used to identify cancerous cells atdifferent stages of development. The antibodies may also be used todetermine which individuals' tumors express the antigen on their surfaceat a pre-determined level and are thus candidates for immunotherapyusing antibodies directed against said antigen. The antibodies mayrecognize both primary and metastasizing cancers of the kidney, ovary,prostate and pancreas and primary cancers of the lung that expressKID31. As used herein, detection may include qualitative and/orquantitative detection and may include comparing the level measured to anormal cell for an increased level of expression of KID31 in cancerouscells.

The invention also provides methods of aiding diagnosis of cancer (suchas ovarian, lung, pancreatic, prostate, colon, or breast cancer) in anindividual using any antibody that binds to KID31 and any other methodsthat can be used determine the level of KID31 expression. As usedherein, methods for “aiding diagnosis” means that these methods assistin making a clinical determination regarding the classification, ornature, of cancer, and may or may not be conclusive with respect to thedefinitive diagnosis. Accordingly, a method of aiding diagnosis ofcancer can comprise the step of detecting the level of KID31 in abiological sample from the individual and/or determining the level ofKID31 expression in the sample. Antibodies recognizing the antigen or aportion thereof may also be used to create diagnostic immunoassays fordetecting antigen released or secreted from living or dying cancer cellsin bodily fluids, including but not limited to, blood, saliva, urine,pulmonary fluid, or ascites fluid.

Not all cells in a particular tumor of interest will express KID31, andcancerous cells in other tissues may express KID31, thus an individualshould be screened for the presence or absence of KID31 on cancerouscells to determine the usefulness of immunotherapy in the individual.The anti-KID31 antibodies made by the methods disclosed herein may beused to determine whether an individual diagnosed with cancer may bedeemed a candidate for immunotherapy using antibodies directed againstKID31. In one embodiment, a cancerous tumor or a biopsy sample may betested for expression of KID31, using antibodies directed against KID31.Individuals with cancer cells that express KID31 are suitable candidatesfor immunotherapy using antibodies directed against KID31. Staining withanti-KID31 antibody may also be used to distinguish cancerous tissuesfrom normal tissues.

Methods of using anti-KID31 antibodies for diagnostic purposes areuseful both before and after any form of anti-cancer treatment, e.g.,chemotherapy or radiation therapy, to determine which tumors are mostlikely to respond to a given treatment, prognosis for individual withcancer, tumor subtype or origin of metastatic disease, and progressionof the disease or response to treatment.

The compositions of this invention are also suitable for diagnosis ofdisease states other than cancer, using the methods generally describedabove in application with other diseased (non-cancerous) cells. Diseasestates suitable for use in the methods of this invention include, butare not limited to, diseases or disorders associated with inflammatoryor autoimmune responses in individuals.

The methods described above may be used for modulating inflammatory orautoimmune responses in individuals. Diseases and conditions resultingfrom inflammation and autoimmune disorders that may be subject todiagnosis and/or treatment using the compositions and methods of theinvention include, by way of illustration and not of limitation,multiple sclerosis, meningitis, encephalitis, stroke, other cerebraltraumas, inflammatory bowel disease including ulcerative colitis andCrohn's disease, myasthenia gravis, lupus, rheumatoid arthritis, asthma,acute juvenile onset diabetes, AIDS dementia, atherosclerosis,nephritis, retinitis, atopic dermatitis, psoriasis, myocardial ischemiaand acute leukocyte-mediated lung injury.

Still other indications for diagnostic and/or therapeutic use ofantibodies and other therapeutic agents of the invention includeadministration to individuals at risk of organ or graft rejection. Overrecent years there has been a considerable improvement in the efficiencyof surgical techniques for transplanting tissues and organs such asskin, kidney, liver, heart, lung, pancreas and bone marrow. Perhaps theprincipal outstanding problem is the lack of satisfactory agents forinducing immunotolerance in the recipient to the transplanted allograftor organ. When allogeneic cells or organs are transplanted into a host(i.e., the donor and donee are different individuals from the samespecies), the host immune system is likely to mount an immune responseto foreign antigens in the transplant (host-versus-graft disease)leading to destruction of the transplanted tissue.

Uses described anywhere in this application that recite their use foranti-KID31 antibodies also encompass the use of other KID31 agonists,antagonists and modulators as described herein. In such embodiments, theKID31 agonists, antagonist or other non-antibody modulator issubstituted for the KID31 antibody in the steps described, andalterations within the scope of the ordinarily skilled practitioner aremade to tailor the method to the substituted KID31 modulatorycomposition.

VII. Compositions of this Invention

This invention also encompasses compositions, including pharmaceuticalcompositions, comprising anti-KID31 antibodies, polypeptides derivedfrom anti-KID31 antibodies, polynucleotides comprising sequence encodinganti-KID31 antibodies, and other agents as described herein. As usedherein, compositions further comprises one or more antibodies,polypeptides and/or proteins that bind to KID31, KID31 agonists,antagonists, modulators, and/or one or more polynucleotides comprisingsequences encoding one or more antibodies, polypeptides and proteinsthat bind to KID31.

The invention further provides for conjugates of any KID31 peptideagonist, antagonist or modulator, and additional chemical structuresthat support the intended function or functions of the particular KID31peptide agonist, antagonist or modulator. These conjugates include KID31peptide agonist, antagonist or modulator covalently bound to amacromolecule such as any insoluble, solid support matrix used in thediagnostic, screening or purification procedures discussed herein.Suitable matrix materials include any substance that is chemicallyinert, has high porosity and has large numbers of functional groupscapable of forming covalent linkages with peptide ligands. Examples ofmatrix materials and procedures for preparation of matrix-ligandconjugates are described in Dean et al. (eds) Affinity Chromatography: APractical Approach, IRL Press (1985); Lowe, “An Introduction to AffinityChromatography”, in Work et al. (eds) Laboratory Techniques inBiochemistry and Molecular Biology, Vol. 7, Part II, North-Holland(1979); Porath et al., “Biospecific Affinity Chromatography”, in Neurathet al. (eds), The Proteins, 3rd ed., Vol. 1, pp. 95-178 (1975); andSchott, Affinity Chromatography, Dekker (1984).

Also provided herein are conjugates of KID31 peptide agonist, antagonistor modulator and any reporter moiety used in the diagnostic proceduresdiscussed herein.

The KID31 peptide agonist, antagonist or modulator agents, polypeptidesand proteins of this invention, including anti-KID31 antibodies, arefurther identified and characterized by any (one or more) of thefollowing criteria: (a) ability to bind to KID31 (including KID31 oncancer cells, including but not limited to ovarian, prostate,pancreatic, lung, colon, or breast cancer cells); (b) ability tocompetitively inhibits preferential binding of a known anti-KID31antibody to KID31, including the ability to preferentially bind to thesame KID31 epitope to which the original antibody preferentially binds;(c) ability to bind to a portion of KID31 that is exposed on the surfaceof a living cell in vitro or in vivo; (d) ability to bind to a portionof KID31 that is exposed on the surface of living cancer cells, such asbut not limited to ovarian, prostate, pancreatic, lung, colon, or breastcancer cells; (e) ability to deliver a chemotherapeutic agent ordetectable marker to cancerous cells (such as but not limited toovarian, prostate, pancreatic, lung, colon, or breast cancer cells)expressing KID31; (f) ability to deliver a therapeutic agent intocancerous cells (such as but not limited to ovarian cancer cells)expressing KID31.

In some embodiments, the antibody of the invention is an antibody thatis produced by a host cell with a deposit number of ATCC Nos. PTA# 6516,or progeny thereof. The present invention also encompasses variousformulations of antibodies produced by these deposited hybridomas andequivalent antibodies or polypeptide fragments (e.g., Fab, Fab′,F(ab′)₂, Fv, Fc, etc.), chimeric antibodies, single chain (ScFv),mutants thereof, fusion proteins comprising an antibody portion,humanized antibodies, and any other modified configuration of any ofthese or equivalent antibodies that comprises an antigen (KID31),recognition site of the required specificity. The invention alsoprovides human antibodies displaying one or more of the biologicalcharacteristics of an anti-KID31 family member. The equivalentantibodies of the anti-KID31 family (including humanized antibodies andhuman antibodies), polypeptide fragments, and polypeptides comprisingany of these fragments are identified and characterized by any (one ormore) of the five criteria described above.

In some embodiments, the antibodies, polypeptides and proteins of theinvention that bind to KID31 are antibodies, polypeptides and proteinsthat competitively inhibit preferential binding of a herein-specifiedanti-KID31 antibody to KID31. In some embodiments, the antibodies, thepolypeptides and the proteins preferentially bind to the same epitope onKID31 as the antibody mu-anti-KID31 preferentially binds.

Accordingly, the invention provides any of the following (orcompositions, including pharmaceutical compositions, comprising any ofthe following): (a) an antibody produced by the host cell with a depositnumber identified above or its progeny; (b) a humanized form of such anantibody; (c) an antibody comprising one or more of the light chainand/or heavy chain variable regions of such an antibody; (d) a chimericantibody comprising variable regions homologous or derived from variableregions of a heavy chain and a light chain of such an antibody, andconstant regions homologous or derived from constant regions of a heavychain and a light chain of a human antibody; (e) an antibody comprisingone or more of the light chain and/or heavy chain CDRs (at least one,two, three, four, five, or six) of such an antibody; (f) an antibodycomprising a heavy and/or a light chain of such an antibody; (g) a humanantibody that is equivalent to such an antibody. A humanized form of theantibody may or may not have CDRs identical to that original antibody,or antibody produced by a host cell with a deposit number identifiedabove. Determination of CDR regions is well within the skill of the art.In some embodiments, the invention provides an antibody which comprisesat least one CDR that is substantially homologous to at least one CDR,at least two, at least three, at least four, at least 5 CDRs of anantibody produced by one of the above-identified deposited hybridomas(or, in some embodiments substantially homologous to all 6 CDRs of oneof these antibodies, or derived from one of these antibodies), orantibody produced by the host cell with a deposit number identifiedabove. Other embodiments include antibodies that have at least two,three, four, five, or six CDR(s) that are substantially homologous to atleast two, three, four, five or six CDRs of an antibody produced from ahybridoma deposited as identified herein, or derived from such anantibody. It is understood that, for purposes of this invention, bindingspecificity and/or overall activity (which may be in terms of deliveringa chemotherapeutic agent to or into cancerous cells to reduce the growthand/or proliferation of cancer cells, to induce apoptotic cell death inthe cancer cell, to delay the development of metastasis, and/or treatingpalliatively) is generally retained, although the extent of activity mayvary compared to an antibody produced by a deposited hybridoma (may begreater or lesser). The invention also provides methods of making any ofthese antibodies. Methods of making antibodies are known in the art andare described herein.

The invention also provides polypeptides comprising an amino acidsequence of the antibodies of the invention. In some embodiments, thepolypeptide comprises one or more of the light chain and/or heavy chainvariable regions of the antibody. In some embodiments, the polypeptidecomprises one or more of the light chain and/or heavy chain CDRs of theantibody. In some embodiments, the polypeptide comprises three CDRs ofthe light chain and/or heavy chain of the antibody. In some embodiments,the polypeptide comprises an amino acid sequence of the antibody thathas any of the following: at least 5 contiguous amino acids of asequence of the original antibody, at least 8 contiguous amino acids, atleast about 10 contiguous amino acids, at least about 15 contiguousamino acids, at least about 20 contiguous amino acids, at least about 25contiguous amino acids, at least about 30 contiguous amino acids,wherein at least 3 of the amino acids are from a variable region of theantibody. In one embodiment, the variable region is from a light chainof the original antibody. In another embodiment, the variable region isfrom a heavy chain of the antibody. In another embodiment, the 5 (ormore) contiguous amino acids are from a complementarity-determiningregion (CDR) of the antibody.

In some embodiments of this invention, cells of this invention thatexpress KID31, a portion of KID31, anti-KID31 antibodies or otherKID31-binding polypeptides of this invention are administered directlyto an individual to modulate their in vivo KID31 biological activity.

VIII. Methods of Using KID31 Modulators and Anti-KID31 Antibodies forTherapeutic Purposes

Monoclonal antibodies to KID31 may be used for therapeutic purposes inindividuals with cancer or other diseases. Therapy with anti-KID31antibodies can involve formation of complexes both in vitro and in vivoas described above. In one embodiment, monoclonal antibody anti-KID31can bind to and reduce the proliferation of cancerous cells. It isunderstood that the antibody is administered at a concentration thatpromotes binding at physiological (e.g., in vivo) conditions. In anotherembodiment, monoclonal antibodies to KID31 can be used for immunotherapydirected at cancerous cells of different tissues such as lung, kidney,pancreatic, ovarian, and colon and other types of cancer such assarcoma. In another embodiment, monoclonal antibody anti-KID31 alone canbind to and reduce cell division in the cancer cell. In anotherembodiment, monoclonal antibody anti-KID31 can bind to cancerous cellsand delay the development of metastasis. In yet another embodiment, anindividual with cancer is given palliative treatment with anti-KID31antibody. Palliative treatment of a cancer individual involves treatingor lessening the adverse symptoms of the disease, or iatrogenic symptomsresulting from other treatments given for the disease without directlyaffecting the cancer progression. This includes treatments for easing ofpain, nutritional support, sexual problems, psychological distress,depression, fatigue, psychiatric disorders, nausea, vomiting, etc.

In such situations, the anti-KID31 antibody may be administered withagents that enhance or direct an individual's own immune response, suchas an agent that strengthens antibody-dependent cellular cytotoxicity(ADCC). In other embodiments, at least one fucose residue present in ananti-KID31 antibody is removed from the oligosaccharides of thatantibody, a modification to enhance ADCC. In similar embodiments, fucoseresidues present in an anti-KID31 antibody are modified to alter theircomposition to the extent required to enhance ADCC compared to theoriginal, unmodified antibody.

In yet another embodiment, anti-KID31 antibody be conjugated to orassociated with a radioactive molecule, toxin (e.g., calicheamicin),chemotherapeutic molecule, liposomes or other vesicles containingchemotherapeutic compounds and administered to an individual in need ofsuch treatment to target these compounds to the cancer cell containingthe antigen recognized by the antibody and thus eliminate cancerous ordiseased cells. Without being limited to any particular theory, theanti-KID31 antibody is internalized by the cell bearing KID31 at itssurface, thus delivering the conjugated moiety to the cell to induce thetherapeutic effect. In yet another embodiment, the antibody can beemployed as adjuvant therapy at the time of the surgical removal of acancer expressing the antigen in order to delay the development ofmetastasis. The antibody can also be administered before surgery(neoadjuvant therapy) in an individual with a tumor expressing theantigen in order to decrease the size of the tumor and thus enable orsimplify surgery, spare tissue during surgery, and/or decrease theresulting disfigurement.

Cell cycle dosing is contemplated in the practice of this invention. Insuch embodiments, a chemotherapeutic agent is used to synchronize thecell cycle of the tumor or other target diseased cells at apre-determined stage. Subsequently, administration of the anti-KID31antibody of this invention (alone or with an additional therapeuticmoiety) is made. In alternative embodiments, an anti-KID31 antibody isused to synchronize the cell cycle and reduce cell division prior toadministration of a second round of treatment; the second round may beadministration of an anti-KID31 antibody and/or an additionaltherapeutic moiety.

Chemotherapeutic agents include radioactive molecules, toxins, alsoreferred to as cytotoxins or cytotoxic agents, which includes any agentthat is detrimental to the viability of cancerous cells, agents, andliposomes or other vesicles containing chemotherapeutic compounds.Examples of suitable chemotherapeutic agents include but are not limitedto 1-dehydrotestosterone, 5-fluorouracil decarbazine, 6-mercaptopurine,6-thioguanine, actinomycin D, adriamycin, aldesleukin, alkylatingagents, allopurinol sodium, altretamine, amifostine, anastrozole,anthramycin (AMC)), anti-mitotic agents, cis-dichlorodiamine platinum(II) (DDP) cisplatin), diamino dichloro platinum, anthracyclines,antibiotics, antimetabolites, asparaginase, BCG live (intravesical),betamethasone sodium phosphate and betamethasone acetate, bicalutamide,bleomycin sulfate, busulfan, calcium leucouorin, calicheamicin,capecitabine, carboplatin, lomustine (CCNU), carmustine (BSNU),Chlorambucil, Cisplatin, Cladribine, Colchicin, conjugated estrogens,Cyclophosphamide, Cyclothosphamide, Cytarabine, Cytarabine, cytochalasinB, Cytoxan, Dacarbazine, Dactinomycin, dactinomycin (formerlyactinomycin), daunirubicin HCL, daunorucbicin citrate, denileukindiftitox, Dexrazoxane, Dibromomannitol, dihydroxy anthracin dione,Docetaxel, dolasetron mesylate, doxorubicin HCL, dronabinol, E. coliL-asparaginase, emetine, epoetin alfa, Erwinia L-asparaginase,esterified estrogens, estradiol, estramustine phosphate sodium, ethidiumbromide, ethinyl estradiol, etidronate, etoposide citrororum factor,etoposide phosphate, filgrastim, floxuridine, fluconazole, fludarabinephosphate, fluorouracil, flutamide, folinic acid, gemcitabine HCL,glucocorticoids, goserelin acetate, gramicidin D, granisetron HCL,hydroxyurea, idarubicin HCL, ifosfamide, interferon alfa-2b, irinotecanHCL, letrozole, leucovorin calcium, leuprolide acetate, levamisole HCL,lidocaine, lomustine, maytansinoid, mechlorethamine HCL,medroxyprogesterone acetate, megestrol acetate, melphalan HCL,mercaptipurine, mesna, methotrexate, methyltestosterone, mithramycin,mitomycin C, mitotane, mitoxantrone, nilutamide, octreotide acetate,ondansetron HCL, paclitaxel, pamidronate disodium, pentostatin,pilocarpine HCL, plimycin, polifeprosan 20 with carmustine implant,porfimer sodium, procaine, procarbazine HCL, propranolol, rituximab,sargramostim, streptozotocin, tamoxifen, taxol, teniposide, tenoposide,testolactone, tetracaine, thioepa chlorambucil, thioguanine, thiotepa,topotecan HCL, toremifene citrate, trastuzumab, tretinoin, valrubicin,vinblastine sulfate, vincristine sulfate, and vinorelbine tartrate.

In a preferred embodiment, the cytotoxin is especially effective individing or rapidly dividing cells, such that non-dividing cells arerelatively spared from the toxic effects.

The antibodies of the invention can be internalized within the diseasedor carcinoma cells to which they bind and are therefore particularlyuseful for therapeutic applications, for example, delivering into thecells toxins that need to be internalized for their adverse activity.Examples of such toxins include, but not limited to, saporin,calicheamicin, auristatin, and maytansinoid.

The antibodies or polypeptides of the invention can be associated(including conjugated or linked) to a radioactive molecule, a toxin, orother therapeutic agents, or to liposomes or other vesicles containingtherapeutic agents covalently or non-covalently, directly or indirectly.The antibody may be linked to the radioactive molecule, the toxin, orthe chemotherapeutic molecule at any location along the antibody so longas the antibody is able to bind its target KID31.

A toxin or a chemotherapeutic agent may be coupled (e.g., covalentlybonded) to a suitable monoclonal antibody either directly or indirectly(e.g., via a linker group, or, alternatively, via a linking moleculewith appropriate attachment sites, such as a platform molecule asdescribed in U.S. Pat. No. 5,552,391). The toxin and chemotherapeuticagent of the present invention can be coupled directly to the particulartargeting proteins using methods known in the art. For example, a directreaction between an agent and an antibody is possible when eachpossesses a substituent capable of reacting with the other. For example,a nucleophilic group, such as an amino or sulfhydryl group, on one maybe capable of reacting with a carbonyl-containing group, such as ananhydride or an acid halide, or with an alkyl group containing a goodleaving group (e.g., a halide) on the other.

The antibodies or polypeptides can also be linked to a chemotherapeuticagent via a microcarrier. Microcarrier refers to a biodegradable or anon-biodegradable particle which is insoluble in water and which has asize of less than about 150, 120 or 100 mm in size, more commonly lessthan about 50-60 μm, preferably less than about 10, 5, 2.5, 2 or 1.5 μm.Microcarriers include “nanocarriers”, which are microcarriers have asize of less than about 1 μm, preferably less than about 500 nm. Suchparticles are known in the art. Solid phase microcarriers may beparticles formed from biocompatible naturally occurring polymers,synthetic polymers or synthetic copolymers, which may include or excludemicrocarriers formed from agarose or cross-linked agarose, as well asother biodegradable materials known in the art. Biodegradable solidphase microcarriers may be formed from polymers which are degradable(e.g., poly(lactic acid), poly(glycolic acid) and copolymers thereof) orerodible (e.g., poly(ortho esters such as3,9-diethylidene-2,4,8,10-tetraoxaspiro[5.5]undecane (DETOSU) orpoly(anhydrides), such as poly(anhydrides) of sebacic acid) undermammalian physiological conditions. Microcarriers may also be liquidphase (e.g., oil or lipid based), such liposomes, iscoms(immune-stimulating complexes, which are stable complexes ofcholesterol, and phospholipid, adjuvant-active saponin) without antigen,or droplets or micelles found in oil-in-water or water-in-oil emulsions,provided the liquid phase microcarriers are biodegradable. Biodegradableliquid phase microcarriers typically incorporate a biodegradable oil, anumber of which are known in the art, including squalene and vegetableoils. Microcarriers are typically spherical in shape, but microcarriersthat deviate from spherical shape are also acceptable (e.g., ellipsoid,rod-shaped, etc.). Due to their insoluble nature (with respect towater), microcarriers are filterable from water and water-based(aqueous) solutions.

The antibody or polypeptide conjugates of the present invention mayinclude a bifunctional linker that contains both a group capable ofcoupling to a toxic agent or chemotherapeutic agent and a group capableof coupling to the antibody. A linker can function as a spacer todistance an antibody from an agent in order to avoid interference withbinding capabilities. A linker can be cleavable or non-cleavable. Alinker can also serve to increase the chemical reactivity of asubstituent on an agent or an antibody, and thus increase the couplingefficiency. An increase in chemical reactivity may also facilitate theuse of agents, or functional groups on agents, which otherwise would notbe possible. The bifunctional linker can be coupled to the antibody bymeans that are known in the art. For example, a linker containing anactive ester moiety, such as an N-hydroxysuccinimide ester, can be usedfor coupling to lysine residues in the antibody via an amide linkage. Inanother example, a linker containing a nucleophilic amine or hydrazineresidue can be coupled to aldehyde groups produced by glycolyticoxidation of antibody carbohydrate residues. In addition to these directmethods of coupling, the linker can be indirectly coupled to theantibody by means of an intermediate carrier such as an aminodextran. Inthese embodiments the modified linkage is via either lysine,carbohydrate, or an intermediate carrier. In one embodiment, the linkeris coupled site-selectively to free thiol residues in the protein.Moieties that are suitable for selective coupling to thiol groups onproteins are well known in the art. Examples include disulfidecompounds, α-halocarbonyl and α-halocarboxyl compounds, and maleimides.When a nucleophilic amine function is present in the same molecule as anα-halo carbonyl or carboxyl group the potential exists for cyclizationto occur via intramolecular alkylation of the amine. Methods to preventthis problem are well known to one of ordinary skill in the art, forexample by preparation of molecules in which the amine and α-halofunctions are separated by inflexible groups, such as aryl groups ortrans-alkenes, that make the undesired cyclization stereochemicallydisfavored. See, for example, U.S. Pat. No. 6,441,163 for preparation ofconjugates of maytansinoids and antibody via a disulfide moiety.

One of the cleavable linkers that can be used for the preparation ofantibody-drug conjugates is an acid-labile linker based on cis-aconiticacid that takes advantage of the acidic environment of differentintracellular compartments such as the endosomes encountered duringreceptor mediated endocytosis and the lysosomes. See, for example, Shenet al., Biochem. Biophys. Res. Commun. 102:1048-1054 (1981) for thepreparation of conjugates of daunorubicin with macromolecular carriers;Yang et al., J. Natl. Canc. Inst. 80:1154-1159 (1988) for thepreparation of conjugates of daunorubicin to an anti-melanoma antibody;Dillman et al., Cancer Res. 48:6097-6102 (1988) for using an acid-labilelinker in a similar fashion to prepare conjugates of daunorubicin withan anti-T cell antibody; Trouet et al., Proc. Natl. Acad. Sci.79:626-629 (1982) for linking daunorubicin to an antibody via a peptidespacer arm.

An antibody (or polypeptide) of this invention may be conjugated(linked) to a radioactive molecule by any method known to the art. For adiscussion of methods for radiolabeling antibody see “Cancer Therapywith Monoclonal AntibodiesT”, D. M. Goldenberg ed. (CRC Press, BocaRaton, 1995).

Alternatively, an antibody can be conjugated to a second antibody toform an antibody heteroconjugate as described by Segal in U.S. Pat. No.4,676,980. The formation of cross-linked antibodies can target theimmune system to specific types of cells, for example, cancer ordiseased cells expressing KID31.

This invention also provides methods of delaying development ofmetastasis in an individual with cancer (including, but not limited to,lung, kidney, pancreatic, ovarian, and colon cancer) using an anti-KID31antibody or other embodiments that bind to KID31 linked to achemotherapeutic agent. In some embodiments, the antibody is a humanizedor chimeric form of a non-human anti-KID31 antibody.

In yet another embodiment, the antibody can be employed as adjuvanttherapy at the time of the surgical removal of a cancer expressing theantigen in order to delay the development of metastasis. The antibody orantibody associated with a chemotherapeutic agent can also beadministered before surgery (neoadjuvant therapy) in an individual witha tumor expressing the antigen in order to decrease the size of thetumor and thus enable or simplify surgery, spare tissue during surgery,and/or decrease the resulting disfigurement.

In yet another embodiment, any of the KID31 binding embodimentsdescribed herein can bind to KID31-expressing cancerous cells andinduces an active immune response against the cancerous cells expressingKID31. In some cases, the active immune response can cause the death ofthe cancerous cells (e.g., antibody binding to cancer cells inducingapoptotic cell death), or inhibit the growth (e.g., block cells cycleprogression) of the cancerous cells. In other cases, any of the novelantibodies described herein can bind to cancerous cells and antibodydependent cellular cytotoxicity (ADCC) can eliminate cancerous cells towhich anti-KID31 binds. Accordingly, the invention provides methods ofstimulating an immune response comprising administering any of thecompositions described herein.

In some cases, antibody binding can also activate both cellular andhumoral immune responses and recruit more natural killer cells orincreased production of cytokines (e.g., IL-2, IFN-g, IL-12, TNF-a,TNF-b, etc.) that further activate an individual's immune system todestroy cancerous cells. In yet another embodiment, anti-KID31antibodies can bind to cancerous cells, and macrophages or otherphagocytic cell can opsonize the cancerous cells.

Various formulations of anti-KID31 antibodies or fragments thereof maybe used for administration. In some embodiments, anti-KID31 antibodiesor fragments thereof may be administered neat. In addition to thepharmacologically active agent, the compositions of the presentinvention may contain suitable pharmaceutically acceptable carrierscomprising excipients and auxiliaries that are well known in the art andare relatively inert substances that facilitate administration of apharmacologically effective substance or which facilitate processing ofthe active compounds into preparations that can be used pharmaceuticallyfor delivery to the site of action. For example, an excipient can giveform or consistency, or act as a diluent. Suitable excipients includebut are not limited to stabilizing agents, wetting and emulsifyingagents, salts for varying osmolarity, encapsulating agents, buffers, andskin penetration enhancers.

Suitable formulations for parenteral administration include aqueoussolutions of the active compounds in water-soluble form, for example,water-soluble salts. In addition, suspensions of the active compounds asappropriate for oily injection suspensions may be administered. Suitablelipophilic solvents or vehicles include fatty oils, for example, sesameoil, or synthetic fatty acid esters, for example, ethyl oleate ortriglycerides. Aqueous injection suspensions may contain substances thatincrease the viscosity of the suspension and include, for example,sodium carboxymethyl cellulose, sorbitol, and/or dextran. Optionally,the suspension may also contain stabilizers. Liposomes can also be usedto encapsulate the agent for delivery into the cell.

The pharmaceutical formulation for systemic administration according tothe invention may be formulated for enteral, parenteral or topicaladministration. Indeed, all three types of formulation may be usedsimultaneously to achieve systemic administration of the activeingredient. Excipients as well as formulations for parenteral andnonparenteral drug delivery are set forth in Remington, The Science andPractice of Pharmacy 20th Ed. Mack Publishing (2000).

Suitable formulations for oral administration include hard or softgelatin capsules, pills, tablets, including coated tablets, elixirs,suspensions, syrups or inhalations and controlled release forms thereof.

Generally, these agents are formulated for administration by injection(e.g., intraperitoneally, intravenously, subcutaneously,intramuscularly, etc.), although other forms of administration (e.g.,oral, mucosal, etc) can be also used. Accordingly, anti-KID31 antibodiesare preferably combined with pharmaceutically acceptable vehicles suchas saline, Ringer's solution, dextrose solution, and the like.

The particular dosage regimen, i.e., dose, timing and repetition, willdepend on the particular individual and that individual's medicalhistory. Generally, a dose of at least about 100 ug/kg body weight, morepreferably at least about 250 ug/kg body weight, even more preferably atleast about 750 ug/kg body weight, even more preferably at least about 3mg/kg body weight, even more preferably at least about 5 mg/kg bodyweight, even more preferably at least about 10 mg/kg body weight isadministered.

Empirical considerations, such as the half-life, generally willcontribute to the determination of the dosage. Antibodies, which arecompatible with the human immune system, such as humanized antibodies orfully human antibodies, may be used to prolong half-life of the antibodyand to prevent the antibody being attacked by the host's immune system.Frequency of administration may be determined and adjusted over thecourse of therapy, and is based on reducing the number of cancerouscells, maintaining the reduction of cancerous cells, reducing theproliferation of cancerous cells, or delaying the development ofmetastasis. Alternatively, sustained continuous release formulations ofanti-KID31 antibodies may be appropriate. Various formulations anddevices for achieving sustained release are known in the art.

In one embodiment, dosages for anti-KID31 antibodies may be determinedempirically in individuals who have been given one or moreadministration(s). Individuals are given incremental dosages of ananti-KID31 antibody. To assess efficacy of anti-KID31 antibodies, amarker of the specific cancer disease state can be followed. Theseinclude direct measurements of tumor size via palpation or visualobservation, indirect measurement of tumor size by x-ray or otherimaging techniques; an improvement as assessed by direct tumor biopsyand microscopic examination of the tumor sample; the measurement of anindirect tumor marker (e.g., PSA for prostate cancer), a decrease inpain or paralysis; improved speech, vision, breathing or otherdisability associated with the tumor; increased appetite; or an increasein quality of life as measured by accepted tests or prolongation ofsurvival. It will be apparent to one of skill in the art that the dosagewill vary depending on the individual, the type of cancer, the stage ofcancer, whether the cancer has begun to metastasize to other location inthe individual, and the past and concurrent treatments being used.

Other formulations include suitable delivery forms known in the artincluding, but not limited to, carriers such as liposomes. See, forexample, Mahato et al. (1997) Pharm. Res. 14:853-859. Liposomalpreparations include, but are not limited to, cytofectins, multilamellarvesicles and unilamellar vesicles.

In some embodiments, more than one antibody may be present. Theantibodies can be monoclonal or polyclonal. Such compositions maycontain at least one, at least two, at least three, at least four, atleast five different antibodies that are reactive against carcinomas,adenocarcinomas, sarcomas, or adenosarcomas. Anti-KID31 antibody can beadmixed with one or more antibodies reactive against carcinomas,adenocarcinomas, sarcomas, or adenosarcomas in organs including but notlimited to ovary, breast, lung, prostate, colon, kidney, skin, thyroid,bone, upper digestive tract, and pancreas. In one embodiment, a mixtureof different anti-KID31 antibodies are used. A mixture of antibodies, asthey are often denoted in the art, may be particularly useful intreating a broader range of population of individuals.

The following examples are provided to illustrate, but not to limit, theinvention.

EXAMPLES Example 1 Preparation of Human Kidney Cells as an Immunogen

Human fetal kidneys of gestational age between 10 to 18 weeks wereobtained from Advanced Biosciences Research at Alameda County,California. Kidneys were procured and shipped to the lab in tissueculture medium on wet ice. Immediately upon arrival, the kidneys weretransferred to wash medium (cold PBS containing penicillin/streptomycinand gentamycin). The outer membranes were removed with forceps and thekidneys were briefly washed in 70% ethanol then rinsed twice in washmedium. The kidneys were minced into 1 mm cubes with surgical scissorsin a 100 mm dry culture dish. The tissue pieces were plated in 10 ml ofa defined serum-free medium referred to herein as I/3F. This media isdescribed in U.S. Provisional Application No. 60/504,674, the disclosureof which is hereby incorporated by reference. While a variety ofcommonly used cell culture media may be used in the practice of thisinvention, presently preferred embodiments use serum-free,fructose-based cell culture media.

The tissue pieces were transferred into a 15 ml centrifuge tube and thetissue pieces were centrifuged at 1000×g for 5 minutes. The tissuepieces were resuspended in I/3F medium containing insulin (10 ug/ml),transferrin (10 ug/ml), epidermal growth factor (20 ng/ml), somatotropin(0.005 IU/ml), pig pituitary extract (0.2%), chicken serum (0.1%),gentamycin (100 ug/ml), penicillin/streptomycin (1×) andcollagenase/dispase (0.1%) and incubated at 4° C. overnight. Thefollowing day, centrifuge the digested tissue pieces were centrifuged at1000×g for 5 minutes and washed twice with I/3F medium. The pellet wasresuspended in 10 ml I/3F medium containing insulin (10 ug/ml),transferrin (10 ug/ml), epidermal growth factor (20 ng/ml), somatotropin(0.005 IU/ml), pig pituitary extract (0.2%) and chicken serum (0.1%) andcultured in fibronectin-precoated 10 cm plates.

Under these culture conditions, the human fetal kidney cells attached tothe substrate-coated plates and grew as a monolayer. Culture medium waschanged twice weekly.

To harvest the cells, the cell monolayers were rinsed once with calcium-and magnesium-free Hanks saline solution, incubated in 10 mM EDTA inHanks saline solution at 37 C for 15 minutes. The cells were detachedfrom the culture surface by gentle pipetting. The cell suspension waspelleted by centrifugation at 1000×g for 5 minutes. The supernatant wasremoved and cells were resuspended in serum-free medium (I/3F medium)with non-denaturing adjuvant as appropriate.

Example 2 Generation of Monoclonal Antibodies

A non-denaturing adjuvant (Ribi, R730, Corixa, Hamilton Mont.) wasrehydrated to 2 ml in phosphate buffered saline. 100 μl of thisrehydrated adjuvant was then gently mixed with some of the cell pelletfrom Example 1 to be used for immunization. Approximately 10⁶ humanfetal kidney cells per mouse were injected into Balb/c mice via footpad,approximately once or twice a week. The precise immunization schedule isas follows: Day zero, immunization plus Ribi. Day 3, immunization plusRibi. Day 7, immunization plus Ribi. Day 24, immunization minus Ribi.Day 29, immunization minus Ribi. Day 32, immunization minus Ribi. Day36, immunization minus Ribi. Day 44, immunization minus Ribi. Day 51,immunization minus Ribi. Day 69, bleed for titer test. Day 71.immunization plus Ribi. Day 74, immunization plus Ribi. Day 81,immunization plus Ribi. Day 91, prefusion boost (no Ribi). Day 104,harvest nodes for fusion.

At Day 69, a drop of blood was drawn from the tail of each immunizedanimal to test the titer of antibodies against human fetal kidney cellsusing FACS analysis. When the titer reached at least 1:2000, the micewere sacrificed using CO₂ followed by cervical dislocation. Lymph nodeswere harvested for hybridoma preparation.

Lymphocytes from mice were fused with the mouse myeloma line X63-Ag8.653using 35% polyethylene glycol 4000. On day 10 following the fusion, thehybridoma supernatants were screened for the presence of human fetalkidney cells-specific monoclonal antibodies by fluorescence activatedcell sorting (FACS). Conditioned medium from each hybridoma wasincubated for 30 minutes with an aliquot of human fetal kidney cells.After incubation, the cell samples were washed, resuspended in 0.1 mldiluent and incubated with 1 μg/ml of FITC conjugated F(ab′)2 fragmentof goat anti-mouse IgG for 30 min at 4° C. The cells were washed,resuspended in 0.2 ml FACS diluent and analyzed using a FACScan cellanalyzer (Becton Dickinson; San Jose, Calif.). Hybridoma clones wereselected for further expansion, cloning, and characterization based ontheir binding to the surface of the human fetal kidney cells by FACS. Ahybridoma making a monoclonal antibody designated mu-anti-KID31 whichbinds an antigen designated KID31 was selected.

Example 3 Purification of Anti-KID31 Antibodies, Including mu-Anti-KID31

Those hybridomas that produce antibodies that continue to be reactiveagainst the immunizing cells or cell line are scaled for purification ofthe antibody. The following method was used, although other methodscommonly known in the field can also be applicable. Positive hybridomaswere scaled into three T75 flasks. Once confluent, the cells andsupernatant were collected into 50 ml conical tubes and centrifuged. Thesupernatant was aspirated and the cell pellet was washed with F12/DME(50:50) media and re-centrifuged. The cell pellet was resuspended in 50ml growth medium, F12/DME (50:50) containing 1% ultra-low IgG FBS(GIBCO, Invitrogen Corp.), 10 μg/ml rh insulin and 10 μg/mltransferring. Cells were then inoculated into the pouch of a CL1000 (IBSIntegra BioScience), and the outer chamber was filled with 500 ml of thesame growth medium. The outer chamber is changed on day 7 and day 14with fresh growth medium.

The antibody-containing medium was harvested from the cell pouch on day21. 25 ml of the harvested material is mixed 1:1 with load buffer (3MNaCl, 1.5M glycine pH9.0). The material was flowed over a prepared 5 mlcolumn of protein A resin (Amersham). The column was then washed with 20column volumes of phosphate buffered saline (PBS). The antibodies wereeluted with 0.1M glycine, pH 2.8 and neutralized in 20 μl of 3M Tris, pH9.0. The antibodies were then dialyzed and protein concentration wasdetermined by A₂₈₀ readings on a Beckman DU530 spectrophotometer.

In other experiments, the binding of the mu-anti-KID31 antibody to KID31was tested using live cell ELISA. The following method was used,although other methods commonly known in the field are applicable. Cells(HT-29, SKOV3, SKMES-1, SW480, SKBR-3, and HPAFII) were grown in 10%fetal bovine serum (FBS) containing media to confluency on tissueculture treated 96-well plates (Falcon). Cells were washed with PBS andthen incubated with 50 μl of desired antibodies at a desiredconcentration in Hank's Balanced Salt Solution (HBSS) containing 1% BSAand 0.1% sodium azide for 1 hour at room temperature. The cells werethen washed three times with 100 μl per well of HBSS before incubatingwith horseradish peroxidase (HRP) secondary antibody (50 μl per welldiluted in HBSS) for 30 minutes at room temperature. The cells werefinally washed three times with HBSS and the color change substrate (TMBsubstrate, KPL) was added to each well at 100 μl per well. The colorchange reaction was stopped with the addition of 100 μl per well of 1 Mphosphoric acid. The plates were then read at O.D. 450 nm.

Example 4 Biotinylated Immunoprecipitation Analysis of KID31 Expressionin Cancer Cell Lines Colo205 and ES-2.

Colorectal adenocarcinoma cell line Colo205 and ovarian carcinoma cellline ES-2 were grown to confluency on 175 cm² culture dishes. Theconfluent monolayer was washed three times with Hank's Balanced SaltSolution (HBSS+ containing no sodium bicarbonate or phenol red; bufferedwith 10 mM HEPES, pH 7.4; Sigma Chemicals) and biotinylated with 200 μgof sulfo-NHS-LC-biotin (Pierce Endogen) for 30 minutes at roomtemperature. The cells were then washed with HBSS+ containing 0.1M Tris,pH 7.4 (Sigma Chemicals) and incubated in HBSS+ containing 0.1M Tris, pH7.4 for 15 minutes at room temperature. The cells were finally washedthree times with HBSS+ and lysed by incubation for 5 minutes, on ice, inlysis buffer (HBSS+with 2% Triton X-100, 2 mM PMSF, 0.1% sodium azide,and 1 tablet per 5 ml lysis buffer of EDTA free complete mini-proteasecocktail (Roche Molecular Biochemicals)).

Cells were scraped in lysis buffer and lysates collected. Lysates werecentrifuged at 14,000×g for one hour at 4° C. The clarified lysate wasthen pre-cleared for 2 hours at 4° C. with 51 μl of human IgG conjugated(1 mg/ml) CNBr 4 MB Sepharose beads (Amersham Pharmacia). Human IgGbeads were centrifuged and removed, and then the pre-cleared lysate wasthen incubated with monoclonal antibody mu-anti-KID31 conjugated to CNBr4 MB sepharose beads (conjugated at 1 mg/ml) for 2 hours at 4° C. Themu-anti-KID31 beads were centrifuged and removed after the 2 hourincubation. Both the human IgG and the mu-anti-KID31 beads wereindividually washed three times with 1 ml of lysis buffer and thenwashed three times with 1 ml HBSS+. The washed beads were eluted by theaddition of 30 μl of SDS-PAGE sample buffer and boiling at 99° C. for 5minutes.

The samples were then resolved on a 4-20% Novex gradient gel(Invitrogen), and transferred onto 0.2 μm nitrocellulose membrane(Invitrogen) and visualized by western blotting with 5 μg/blot ofmu-anti-KID31.

For detection with HRP conjugated streptavidin, the nitrocellulose wasfirst blocked for 1 hour with blocking buffer (5% non-fat dry milk inTris buffered saline containing 0.05% Tween-20 (TBST, Sigma Chemicals).HRP conjugated streptavidin was diluted into PBST at 1 g/ml and exposedto the nitrocellulose for 30 minutes at room temperature. Thenitrocellulose was then washed three times with PBST beforevisualization with ECL+.

Results using this protocol and mu-anti-KID31 antibodies show a smear ofmolecular weight bands at approximately 60 kDa to 80 kDa under reducingconditions. The smear pattern and molecular weight of the mu-anti-KID31specific bands are consistent with the molecular weight ofcarboxypeptidase M, a glycoprotein with a molecular weight ofapproximately 62 kD.

Example 5 Immunohistochemistry Methods

Frozen tissue samples from cancer patients were embedded in OCT compoundand quick-frozen in isopentane with dry ice. Cryosections were cut witha Leica 3050 CM microtome at thickness of 8-10 μm and thaw-mounted onSuperFrost Plus slides (VWR #48311-703). The sections were fixed with75% acetone/25% ethanol at 10° C. and allowed to air-dry 2-4 hours atroom temperature. The fixed sections were stored at −80° C. until use.

For immunohistochemistry, the tissue sections were retrieved washed inTris buffered 0.05% Tween (TB-T) and blocked in blocking buffer (TB-T,5% normal goat serum and 100 μg/ml avidin) for 30 minutes at roomtemperature. The slides were then incubated with the mu-anti-KID31 andcontrol monoclonal antibodies diluted in blocking buffer (1 μg/ml) for60-90 minutes at room temperature. The sections were then washed threetimes with the blocking buffer. The bound monoclonal antibodies weredetected with a goat anti-mouse IgG+IgM (H+L) F(ab′)²-peroxidaseconjugates and the peroxidase substrate diaminobenzidine (1 mg/ml, Sigmacat. No. D 5637) in 0.1 M sodium acetate buffer pH 5.05 and 0.003%hydrogen peroxide (Sigma cat. No. H1009). The stained slides werecounter-stained with hematoxylin and examined under Nikon microscope.

In some cases, paraffin embedded formaldehyde-fixed tissues were usedfor immunohistochemistry after appropriate antigen retrieval methodswere employed. One such antigen retrieval method is described in Manghamand Isaacson, Histopathology 35:129-33 (1999). Other methods of antigenretrieval and/or detection may be used by one skilled in the art.Results from similar experiments performed using frozen tissues or,where appropriate, fixed tissue with antigen retrieval and polyMICAdetection were performed. The binding of anti-KID31 antibody to avariety of normal and cancer tissues was assessed. In all cases,antibody binding in control fixed tissues was correlated with that offrozen tissues. The results from frozen tissues were only used if thetwo did not match in the controls.

For convenience, a summary of the combined results of severalexperiments using frozen surgical tissue from different sources is shownbelow in Table 1 and Table 2.

TABLE 1 Distribution of KID31 in normal human tissues Tissue TypeResults Skin 1+ sweat ducts; 1+ to 2+ focal staining on sebaceous glandsLiver Negative Kidney 1+ staining on scattered tubules Lung NegativeDuodenum Negative Pancreas Negative (1+ staining on a few ducts) BreastNegative

TABLE 2 Distribution of KID31 in human tumor tissues Tissue Type ResultsColon Negative (1+ focal staining on interstitium) Breast NegativePancreas 1+ to 2+ on tumor Endometrium +/− staining on tumor Kidney +/−staining on tumor; 1+ to 2+ staining on a subset of small vessels LungNegative to 2+ focal staining on tumor Ovary Negative

Example 6 Immunocytochemistry Results

Monoclonal antibody mu-anti-KID31 was used to test reactivity withvarious cell lines from different types of tissues. The results werescored as ‘+’ for weak positive staining, ‘++’ for moderate positivestaining, ‘+++’ for strong positive staining and ‘−’ for negativestaining.

Immunohistochemistry results were obtained using CellArray™ technology,as described in WO 01/43869: Cells from different established cell lineswere removed from the growth surface without using proteases, packed andembedded in OCT compound. The cells were frozen and sectioned, thenstained using a standard IHC protocol.

Results of the binding of the mu-anti-KID31 antibody to variousestablished human normal and tumor cell lines are compiled forconvenience in Table 3. The experiments represented in Table 3 includeLive-cell ELISA and CellArray™ binding experiments using the methodsdescribed herein.

TABLE 3 Immunocytochemistry results Reactivity Reactivity Live Cell Cellline ATCC# Organ Cell Type Cell Array ELISA BT474 HTB-20 Breast Ductalcarcinoma − MCF7 HTB-22 Breast Adenocarcinoma − ES-2 CRL-1978 OvaryCarcinoma + SKOV3 HTB-77 Ovary Adenocarcinoma − +++ SKMES1 HTB-58 LungSquamous carcinoma + +++ CA130 Raven Lung Small cell carcinoma − CaLu3HTB-55 Lung Adenocarcinoma − 9926 Raven Pancreas Adenocarcinoma − AsPC-1CRL-1682 Pancreas Adenocarcinoma − Hs700T HTB-147 PancreasAdenocarcinoma − Colo205 CCL-222 Colon Ascites colorectal −adenocarcinoma HT-29 HTB-38 Colon Colorectal + adenocarcinoma Cos 7CRL-1651 Kidney SV40 Transformed − (African Green Monkey) RL-65CRL-10345 Lung (Rat) − A204 HTB-82 Muscle Rhabdomyosarcoma +/− G292CRL-1423 Bone Osteosarcoma +/− HT1080 CCL-121 Connective Fibrosarcoma −Tissue MG63 CRL-1427 Bone Osteosarcoma − RD CCL-136 MuscleRhabdomyosarcoma +/− RD-ES HTB-166 Bone Ewing's sarcoma − SKES-1 HTB-86Bone Sarcoma − SKLMS-1 HTB-88 Vulva Leiomyosarcoma − SKUT-1 HTB-114Uterus Mesodermal tumor − (mixed) SW684 HTB-91 Connective Fibrosarcoma −Tissue SW872 HTB-92 Connective Liposarcoma − Tissue 786-O CRL-1932Kidney Renal cell carcinoma − A498 HTB-44 Kidney Carcinoma − Caki-2HTB-47 Kidney Clear cell carcinoma ++ 22RV1 CRL-2505 Prostate Carcinoma− DU145 HTB-81 Prostate Adenocarcinoma − LNCaP CRL-1740 ProstateCarcinoma −

Example 9 Effect of mu-Anti-KID31 on Cancer Cell Line H322M

The ability of the antibodies to reduce cell number in vitro when grownas a monolayer can be assessed using cell monolayers grown in thepresence or absence of varying amounts of test or control purifiedantibody and the change in cell number assessed using MTT. MTT is a dyethat measures the activity of mitochondrial enzymes and correlates withrelative viable cell number. Cells of interest were plated and grown inF12/DMEM (1:1) growth medium supplemented with 10% fetal bovine serum in96 well plates. H322M cells were plated at 500, 1000, 2000 or 4000cells/well in triplicate wells of a 96 well dish. Immediately afterplating, mu-anti-KID31 was added. The cells were incubated at 37° C. ina humidified incubator at 5% CO₂ for 5 days. At the end of the assay,MTT was dissolved in PBS (5 mg/ml) and added directly to wells at 1:10dilution. Plates were placed back in incubator for 4 hours. After theincubation, medium was removed and 100 μl DMSO was added to solubilizethe MTT precipitate. Plates were read at O.D. 540 nm.

At 20 μg/ml mu-anti-KID31 inhibited the growth of cancer cell line H322Mapproximately 10% at the plating densities of 1000 and 2000 cells/well.

Example 10 Anti-Tumor Efficacy of mu-Anti-KID31 Antibody in a Sub-RenalCapsule Tumor Model

This study was designed to test the dose-responsive anti-tumor data foran anti-KID31 antibody in a sub-renal capsule tumor model using H322M, anon-small cell lung cancer-derived cell line and Caki-2, a renaltumor-derived cell line. H322M and Caki-2 cells were resuspended at 100million cells/ml of media.

Type 1 rat-tail collagen was prepared by a standard method. Briefly,tails from mature breeding rats were removed and sterilized by soakingin 70% ethanol. The tail skin was removed and the tendons were isolatedand weighed. One gram of tendon produces 100 ml collagen solution, andeach tail yields approximately 1 to 1.5 grams of tendon. To extract thecollagen, the tendons were placed in a dilute acetic acid solution (200μl glacial acetic acid per gram of tendon in 100 ml water) containingpenicillin, streptomycin and fungizone and stirred gently at 4° C. forat least 1 week. The solution was then centrifuged and the collagensupernatant was stored at 4° C. until use.

For this study, 50 μl collagen buttons were prepared by polymerizing therat-tail collagen in a setting solution containing Earle's Balanced SaltSolution (EBSS), NaOH and NaHCO₃. Following polymerization, 5×10⁵ cellswere added per collagen button. The cells were incubated in collagenovernight at 37° C. prior to implantation.

For implantation of the cells under the kidney capsule, mice were fullyanesthetized with tribromoethanol. A pocket was made in the kidneycapsule to allow for the placement of cells, which was made through aparalumbar surgical approach to the right and/or left kidney. In somestudies, both kidneys received xenografts. Following surgery, theanimals were allowed to recover on a heated surface and observed untilfully recovered from the anesthesia. Wound clips were removed ten dayspost-surgery.

For each treatment dose group, mu-anti-KID31 was diluted in PBS to theappropriate concentration to administer 0.01-ml/gram body weight.Control groups received PBS (0.01 ml/gram body weight). Dosing wasinitiated on Day 2 following implantation, and doses of mu-anti-KID31 orPBS control were administered three times weekly as single rapidinjections into the intraperitoneal cavity.

At the end of the dosing period, animals were euthanized and the tumorsand adjacent tissue were removed and incubated in a digestion buffercontaining proteinase K (1.45 mg/ml) and RNase A (0.07 mg/ml) overnightat 55° C. for PCR analysis.

To generate a template for PCR analysis, genomic DNA was isolated fromtumors using Wizard SV Genomic Purification System (Promega) accordingto manufacturer's instructions. Each DNA sample was resuspended in afinal volume of 200 μl.

The amount of human DNA in the tumors was quantitated using real-timePCR on an Applied Biosystems SDS7000 system, with primers and probespecific for the human ribosomal gene RPL19.

Each sample was initially digested with BstX1 to ensure efficientamplification. Each reaction mix contained 5 μl of template DNA, 5 μlTaqman Gold 10× reaction buffer (Applied Biosystems), 5 units BstX1, 4mM MgCl₂, 2.5 mM each deoxynucleotide mix, 250 nM each primer, 150 nMprobe, 1.5 units Taqgold polymerase (Applied Biosystems) and water to afinal volume of 50 μL. The thermal cycle conditions used were 30 minutesat 45° C. for BstX1 digestion, 10 minutes at 95° C. for BstX1inactivation and Taq hot start, followed by 40 cycles of: 95° C. for 20seconds (denaturation) and 60° C. for 1 minute (elongation).

A standard curve was generated using four-fold serial dilutions of humangenomic DNA (BD Biosciences Clonetech) ranging from 400 to 0.09 ngDNA/reaction. Sample DNA concentrations were interpolated from thestandard curve. Each tumor sample was analyzed in triplicate PCRreactions and average DNA concentrations were determined. The resultsare shown in FIG. 1. From these experiments, H322M tumors treated withmu-anti-KID31 showed a 70.4% decrease in the amount of human DNA whencompared to control PBS treated tumors. Caki-2 tumors treated withmu-anti-KID31 showed a 20.6% decrease in the amount of human DNA whencompared to control PBS treated tumors.

It is understood that the examples and embodiments described herein arefor illustrative purposes only and that various modifications or changesin light thereof will be suggested to persons skilled in the art and areto be included within the spirit and purview of this application. Allpublications, patents and patent applications cited herein are herebyincorporated by reference in their entirety for all purposes to the sameextent as if each individual publication, patent or patent applicationwere specifically and individually indicated to be so incorporated byreference.

1. An isolated antibody produced by a host cell with a deposit number ofATCC No. PTA-6516 or progeny thereof, or an antigen-binding fragmentthereof, said antibody specifically binds to carboxypeptidase M.
 2. Anisolated antibody that binds to carboxypeptidase M, comprising the threecomplementarity determining regions from the heavy chain and the threecomplementarity determining regions from the light chain of the antibodyproduced by the cell line having ATCC No. PTA-6516.
 3. The isolatedantibody of claim 2, wherein the isolated antibody is a humanizedantibody.
 4. The isolated antibody of claim 2, wherein the isolatedantibody is a chimeric antibody comprising a heavy chain variable regionand a light chain variable region from the heavy chain and the lightchain variable regions of the antibody produced by the cell line havingATCC No. PTA-6516.
 5. The isolated antibody of claim 4, wherein thechimeric antibody comprises a heavy chain constant region and a lightchain constant region from a human antibody.
 6. The isolated antibody ofclaim 2, wherein the isolated antibody is linked to a therapeutic agent.7. An antigen-binding fragment of the isolated antibody of claim 2,wherein the antigen-binding fragment is selected from the groupconsisting of a Fab, a Fab′, a F(ab′)2 and a Fv; and wherein theantigen-binding fragment retains the binding specificity of the antibodyproduced by the cell line having ATCC No. PTA-6516.
 8. An isolatedantibody that binds to carboxypeptidase M comprising the heavy chainvariable region of the antibody produced by the cell line having ATCCNo. PTA-6516.
 9. An isolated antibody that binds to carboxypeptidase Mcomprising the light chain variable region of the antibody produced bythe cell line having ATCC No. PTA-6516.
 10. A pharmaceutical compositioncomprising the antibody of claim 2 and a pharmaceutically acceptableexcipient.
 11. The pharmaceutical composition of claim 10, wherein thecomposition comprises an additional therapeutic moiety.
 12. Apharmaceutical composition comprising the antigen-binding fragment ofclaim 7 and a pharmaceutically acceptable excipient.
 13. Apharmaceutical composition comprising the isolated antibody of claim 8and a pharmaceutically acceptable excipient.
 14. A pharmaceuticalcomposition comprising the isolated antibody of claim 9 and apharmaceutically acceptable excipient.